TY  - JOUR
AU  - Veljić, Darko
AU  - Rakin, Marko
AU  - Sedmak, Aleksandar
AU  - Radović, Nenad A.
AU  - Međo, Bojan
AU  - Mrdak, Mihailo
AU  - Bajić, Darko
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3739
AB  - The influence of friction stir welding parameters on thermo-mechanical behav-ior of the material during welding is analyzed. An aluminum alloy is considered (Al 2024 T351), and different rotating and welding speeds are applied. The finite element model consists of the working plate (Al alloy), backing plate and welding tool. The influence of the welding conditions on material behavior is taken into account the application of the Johnson-Cook material model. The rotation speed of the tool affects the results. If increased, it contributes to an increase of friction-gen-erated heat intensity. The other component of the generated heat, which stems from the plastic deformation of the material, is negligibly changed. When the welding speed, i.e. tool translation speed, is increased, the intensity of friction-generated heat decreases, while the heat generation due to plastic deforming is becoming more pronounced. Summed, this leads to rather small change of the total genera-tion. The changes of the heat generation influence both the temperature field and reaction force. Also, the inadequate selection of welding parameters resulted in occurrence of the defects (pores) in the model.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - Thermo-mechanical analysis of linear welding stage in friction stir welding influence of welding parameters
EP  - 2134
IS  - 3
SP  - 2125
VL  - 26
DO  - 10.2298/TSCI210216186V
ER  - 

@article{
author = "Veljić, Darko and Rakin, Marko and Sedmak, Aleksandar and Radović, Nenad A. and Međo, Bojan and Mrdak, Mihailo and Bajić, Darko",
year = "2022",
abstract = "The influence of friction stir welding parameters on thermo-mechanical behav-ior of the material during welding is analyzed. An aluminum alloy is considered (Al 2024 T351), and different rotating and welding speeds are applied. The finite element model consists of the working plate (Al alloy), backing plate and welding tool. The influence of the welding conditions on material behavior is taken into account the application of the Johnson-Cook material model. The rotation speed of the tool affects the results. If increased, it contributes to an increase of friction-gen-erated heat intensity. The other component of the generated heat, which stems from the plastic deformation of the material, is negligibly changed. When the welding speed, i.e. tool translation speed, is increased, the intensity of friction-generated heat decreases, while the heat generation due to plastic deforming is becoming more pronounced. Summed, this leads to rather small change of the total genera-tion. The changes of the heat generation influence both the temperature field and reaction force. Also, the inadequate selection of welding parameters resulted in occurrence of the defects (pores) in the model.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "Thermo-mechanical analysis of linear welding stage in friction stir welding influence of welding parameters",
pages = "2134-2125",
number = "3",
volume = "26",
doi = "10.2298/TSCI210216186V"
}

Veljić, D., Rakin, M., Sedmak, A., Radović, N. A., Međo, B., Mrdak, M.,& Bajić, D.. (2022). Thermo-mechanical analysis of linear welding stage in friction stir welding influence of welding parameters. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 26(3), 2125-2134.
https://doi.org/10.2298/TSCI210216186V

Veljić D, Rakin M, Sedmak A, Radović NA, Međo B, Mrdak M, Bajić D. Thermo-mechanical analysis of linear welding stage in friction stir welding influence of welding parameters. in Thermal Science. 2022;26(3):2125-2134.
doi:10.2298/TSCI210216186V .

Veljić, Darko, Rakin, Marko, Sedmak, Aleksandar, Radović, Nenad A., Međo, Bojan, Mrdak, Mihailo, Bajić, Darko, "Thermo-mechanical analysis of linear welding stage in friction stir welding influence of welding parameters" in Thermal Science, 26, no. 3 (2022):2125-2134,
https://doi.org/10.2298/TSCI210216186V . .

TY  - GEN
AU  - Petrović, Andrija
AU  - Filipović, Jovan
AU  - Petrović, Aleksandar
AU  - Bakić, Gordana
AU  - Veljić, Darko
AU  - Bugarić, Uglješa
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5842
AB  - Ејекторска пумпа за хидротранспорт високо абразивне шљаке и пепела
првенствено је намењена за избацивање шљаке и пепела из котлова, као примарни систем
за транспорт или као секундарни систем за транспорт (уколико већ постоје тзв Д пумпе).
Овакав тип ејекторске пумпе може се врло лако димензионо прилагодити било ком типу
котла и било каквој врсти абразивних материјала (сачма, песак итд.)
T2  - Техничко решење (M82) је прихваћено од стране Матичног научног одбора за машинство и индустријски софтвер, 2020
T1  - Ејекторска пумпа за хидро транспорт високо абразивне шљаке и пепела
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5842
ER  - 

@misc{
author = "Petrović, Andrija and Filipović, Jovan and Petrović, Aleksandar and Bakić, Gordana and Veljić, Darko and Bugarić, Uglješa",
year = "2020",
abstract = "Ејекторска пумпа за хидротранспорт високо абразивне шљаке и пепела
првенствено је намењена за избацивање шљаке и пепела из котлова, као примарни систем
за транспорт или као секундарни систем за транспорт (уколико већ постоје тзв Д пумпе).
Овакав тип ејекторске пумпе може се врло лако димензионо прилагодити било ком типу
котла и било каквој врсти абразивних материјала (сачма, песак итд.)",
journal = "Техничко решење (M82) је прихваћено од стране Матичног научног одбора за машинство и индустријски софтвер, 2020",
title = "Ејекторска пумпа за хидро транспорт високо абразивне шљаке и пепела",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5842"
}

Petrović, A., Filipović, J., Petrović, A., Bakić, G., Veljić, D.,& Bugarić, U.. (2020). Ејекторска пумпа за хидро транспорт високо абразивне шљаке и пепела. in Техничко решење (M82) је прихваћено од стране Матичног научног одбора за машинство и индустријски софтвер, 2020.
https://hdl.handle.net/21.15107/rcub_machinery_5842

Petrović A, Filipović J, Petrović A, Bakić G, Veljić D, Bugarić U. Ејекторска пумпа за хидро транспорт високо абразивне шљаке и пепела. in Техничко решење (M82) је прихваћено од стране Матичног научног одбора за машинство и индустријски софтвер, 2020. 2020;.
https://hdl.handle.net/21.15107/rcub_machinery_5842 .

Petrović, Andrija, Filipović, Jovan, Petrović, Aleksandar, Bakić, Gordana, Veljić, Darko, Bugarić, Uglješa, "Ејекторска пумпа за хидро транспорт високо абразивне шљаке и пепела" in Техничко решење (M82) је прихваћено од стране Матичног научног одбора за машинство и индустријски софтвер, 2020 (2020),
https://hdl.handle.net/21.15107/rcub_machinery_5842 .

TY  - JOUR
AU  - Veljić, Darko
AU  - Rakin, Marko
AU  - Međo, Bojan
AU  - Mrdak, Mihailo
AU  - Sedmak, Aleksandar
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3190
AB  - Friction stir welding is one of the procedures for joining the parts in solid state. Thermo-mechanical simulation of the friction stir welding of high-strength aluminium alloys 2024 T3 and 2024 T351 is considered in this work. Numerical models corresponding to the linear welding stage are developed in Abaqus software package. The material behaviour is modelled by Johnson-Cook law (which relates the yield stress with temperature, strain and strain rate), and the Arbitrary Lagrangian-Eulerian technique is applied. The difference in thermo-mechanical behaviour between the two materials has been analysed and commented. The main quantities which are considered are the temperature in the weld area, plastic strain, as well as the rate of heat generation during the welding process.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - Temperature fields in linear stage of friction stir welding effect of different material properties
EP  - 3992
IS  - 6
SP  - 3985
VL  - 23
DO  - 10.2298/TSCI181015264V
ER  - 

@article{
author = "Veljić, Darko and Rakin, Marko and Međo, Bojan and Mrdak, Mihailo and Sedmak, Aleksandar",
year = "2019",
abstract = "Friction stir welding is one of the procedures for joining the parts in solid state. Thermo-mechanical simulation of the friction stir welding of high-strength aluminium alloys 2024 T3 and 2024 T351 is considered in this work. Numerical models corresponding to the linear welding stage are developed in Abaqus software package. The material behaviour is modelled by Johnson-Cook law (which relates the yield stress with temperature, strain and strain rate), and the Arbitrary Lagrangian-Eulerian technique is applied. The difference in thermo-mechanical behaviour between the two materials has been analysed and commented. The main quantities which are considered are the temperature in the weld area, plastic strain, as well as the rate of heat generation during the welding process.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "Temperature fields in linear stage of friction stir welding effect of different material properties",
pages = "3992-3985",
number = "6",
volume = "23",
doi = "10.2298/TSCI181015264V"
}

Veljić, D., Rakin, M., Međo, B., Mrdak, M.,& Sedmak, A.. (2019). Temperature fields in linear stage of friction stir welding effect of different material properties. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 23(6), 3985-3992.
https://doi.org/10.2298/TSCI181015264V

Veljić D, Rakin M, Međo B, Mrdak M, Sedmak A. Temperature fields in linear stage of friction stir welding effect of different material properties. in Thermal Science. 2019;23(6):3985-3992.
doi:10.2298/TSCI181015264V .

Veljić, Darko, Rakin, Marko, Međo, Bojan, Mrdak, Mihailo, Sedmak, Aleksandar, "Temperature fields in linear stage of friction stir welding effect of different material properties" in Thermal Science, 23, no. 6 (2019):3985-3992,
https://doi.org/10.2298/TSCI181015264V . .

TY  - JOUR
AU  - Musrati, Walid
AU  - Međo, Bojan
AU  - Gubeljak, Nenad
AU  - Stefane, Primoz
AU  - Veljić, Darko
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3030
AB  - The topic of this work is analysis of fracture behaviour and resistance of the thin-walled seamless and seam steel pipes, through application of the recently proposed ring-shaped specimen (PRNB - Pipe Ring Notched Bend). The main loading of these pipes in exploitation is internal pressure, which is why axial defects present a significant threat to their integrity and work safety. The ring-shaped specimen geometry is fairly simple to fabricate from a new or exploited pipeline and the specimens have the same thermo-mechanical treatment, assembly conditions, etc. as the actual structure. Experimental-numerical procedure is applied for prediction of the fracture behaviour; this included material characterisation, testing of ring specimens by bending, as well as micromechanical analysis of ductile fracture. In experimental testing, the deformation of the specimens is monitored by using the stereometric measurement system. Numerical analysis is performed in software package Simulia Abaqus, including the application of the micromechanical Complete Gurson model (CGM). The results obtained in this study, along with some previously published results, lead to conclusion that PRNB specimen is a good option for testing of fracture resistance of cylindrical elements such as pipes.
PB  - Elsevier, Amsterdam
T2  - Theoretical and Applied Fracture Mechanics
T1  - Fracture assessment of seam and seamless steel pipes by application of the ring-shaped bending specimens
VL  - 103
DO  - 10.1016/j.tafmec.2019.102302
ER  - 

@article{
author = "Musrati, Walid and Međo, Bojan and Gubeljak, Nenad and Stefane, Primoz and Veljić, Darko and Sedmak, Aleksandar and Rakin, Marko",
year = "2019",
abstract = "The topic of this work is analysis of fracture behaviour and resistance of the thin-walled seamless and seam steel pipes, through application of the recently proposed ring-shaped specimen (PRNB - Pipe Ring Notched Bend). The main loading of these pipes in exploitation is internal pressure, which is why axial defects present a significant threat to their integrity and work safety. The ring-shaped specimen geometry is fairly simple to fabricate from a new or exploited pipeline and the specimens have the same thermo-mechanical treatment, assembly conditions, etc. as the actual structure. Experimental-numerical procedure is applied for prediction of the fracture behaviour; this included material characterisation, testing of ring specimens by bending, as well as micromechanical analysis of ductile fracture. In experimental testing, the deformation of the specimens is monitored by using the stereometric measurement system. Numerical analysis is performed in software package Simulia Abaqus, including the application of the micromechanical Complete Gurson model (CGM). The results obtained in this study, along with some previously published results, lead to conclusion that PRNB specimen is a good option for testing of fracture resistance of cylindrical elements such as pipes.",
publisher = "Elsevier, Amsterdam",
journal = "Theoretical and Applied Fracture Mechanics",
title = "Fracture assessment of seam and seamless steel pipes by application of the ring-shaped bending specimens",
volume = "103",
doi = "10.1016/j.tafmec.2019.102302"
}

Musrati, W., Međo, B., Gubeljak, N., Stefane, P., Veljić, D., Sedmak, A.,& Rakin, M.. (2019). Fracture assessment of seam and seamless steel pipes by application of the ring-shaped bending specimens. in Theoretical and Applied Fracture Mechanics
Elsevier, Amsterdam., 103.
https://doi.org/10.1016/j.tafmec.2019.102302

Musrati W, Međo B, Gubeljak N, Stefane P, Veljić D, Sedmak A, Rakin M. Fracture assessment of seam and seamless steel pipes by application of the ring-shaped bending specimens. in Theoretical and Applied Fracture Mechanics. 2019;103.
doi:10.1016/j.tafmec.2019.102302 .

Musrati, Walid, Međo, Bojan, Gubeljak, Nenad, Stefane, Primoz, Veljić, Darko, Sedmak, Aleksandar, Rakin, Marko, "Fracture assessment of seam and seamless steel pipes by application of the ring-shaped bending specimens" in Theoretical and Applied Fracture Mechanics, 103 (2019),
https://doi.org/10.1016/j.tafmec.2019.102302 . .

TY  - CONF
AU  - Musrati, Walid
AU  - Međo, Bojan
AU  - Gubeljak, Nenad
AU  - Stefane, Primoz
AU  - Veljić, Darko
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2892
AB  - Application of pipelines is common in process industry and energetic facilities, as parts of storage and transport systems. Structural integrity and fracture resistance of the pipeline elements is typically assessed by testing fracture mechanics specimens, like compact tensile CT or single-edge notched bending, SENB. However, fabrication of these geometries is often not possible for thin-walled pressurized elements, commonly used in structures of process and energetic facilities. Therefore, some proposals for non-standard specimens have been given in the literature, differing by the position of the initial defects, in circumferential or axial direction, and by the degree of complexity of procedures for fabrication and testing. Recently proposed ring-shaped specimen (PRNB - Pipe Ring Notched Bend) is used here to assess the fracture resistance of pressurized cylinders with defects in axial direction, critical for the internal pressure loading. The specimens are simple to fabricate and have the same material history as the actual structure, such as thermo-mechanical treatment, assembly or exploitation conditions. In this work, the ring specimens are cut from the thin-walled non-alloy steel pipes for pressure purposes. Experimental-numerical procedure is applied for prediction of fracture behavior. The methods include material characterization, fracture testing and micromechanical analysis of specimen failure. The results obtained so far lead to conclusion that PRNB specimen is a good option for testing of fracture resistance of pipelines and small-scale vessels.
PB  - Elsevier Science Bv, Amsterdam
C3  - Procedia Structural Integrity - ECF22 - Loading and environmental effects on structural integrity
T1  - Fracture analysis of axially flawed ring-shaped bending specimen
EP  - 1833
SP  - 1828
VL  - 13
DO  - 10.1016/j.prostr.2018.12.333
ER  - 

@conference{
author = "Musrati, Walid and Međo, Bojan and Gubeljak, Nenad and Stefane, Primoz and Veljić, Darko and Sedmak, Aleksandar and Rakin, Marko",
year = "2018",
abstract = "Application of pipelines is common in process industry and energetic facilities, as parts of storage and transport systems. Structural integrity and fracture resistance of the pipeline elements is typically assessed by testing fracture mechanics specimens, like compact tensile CT or single-edge notched bending, SENB. However, fabrication of these geometries is often not possible for thin-walled pressurized elements, commonly used in structures of process and energetic facilities. Therefore, some proposals for non-standard specimens have been given in the literature, differing by the position of the initial defects, in circumferential or axial direction, and by the degree of complexity of procedures for fabrication and testing. Recently proposed ring-shaped specimen (PRNB - Pipe Ring Notched Bend) is used here to assess the fracture resistance of pressurized cylinders with defects in axial direction, critical for the internal pressure loading. The specimens are simple to fabricate and have the same material history as the actual structure, such as thermo-mechanical treatment, assembly or exploitation conditions. In this work, the ring specimens are cut from the thin-walled non-alloy steel pipes for pressure purposes. Experimental-numerical procedure is applied for prediction of fracture behavior. The methods include material characterization, fracture testing and micromechanical analysis of specimen failure. The results obtained so far lead to conclusion that PRNB specimen is a good option for testing of fracture resistance of pipelines and small-scale vessels.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Procedia Structural Integrity - ECF22 - Loading and environmental effects on structural integrity",
title = "Fracture analysis of axially flawed ring-shaped bending specimen",
pages = "1833-1828",
volume = "13",
doi = "10.1016/j.prostr.2018.12.333"
}

Musrati, W., Međo, B., Gubeljak, N., Stefane, P., Veljić, D., Sedmak, A.,& Rakin, M.. (2018). Fracture analysis of axially flawed ring-shaped bending specimen. in Procedia Structural Integrity - ECF22 - Loading and environmental effects on structural integrity
Elsevier Science Bv, Amsterdam., 13, 1828-1833.
https://doi.org/10.1016/j.prostr.2018.12.333

Musrati W, Međo B, Gubeljak N, Stefane P, Veljić D, Sedmak A, Rakin M. Fracture analysis of axially flawed ring-shaped bending specimen. in Procedia Structural Integrity - ECF22 - Loading and environmental effects on structural integrity. 2018;13:1828-1833.
doi:10.1016/j.prostr.2018.12.333 .

Musrati, Walid, Međo, Bojan, Gubeljak, Nenad, Stefane, Primoz, Veljić, Darko, Sedmak, Aleksandar, Rakin, Marko, "Fracture analysis of axially flawed ring-shaped bending specimen" in Procedia Structural Integrity - ECF22 - Loading and environmental effects on structural integrity, 13 (2018):1828-1833,
https://doi.org/10.1016/j.prostr.2018.12.333 . .

TY  - JOUR
AU  - Murariu, Alin
AU  - Veljić, Darko
AU  - Barjaktarević, Dragana R.
AU  - Rakin, Marko
AU  - Radović, Nenad A.
AU  - Sedmak, Aleksandar
AU  - Djoković, Jelena M.
PY  - 2016
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2300
AB  - The heat generated during friction stir welding process depends on plastic deformation of the material and friction between the tool and the material. In this work, heat generation is analysed with respect to the material velocity around the tool in Al alloy Al2024-T351 plate. The slip rate of the tool relative to the workpiece material is related to the frictional heat generated. The material velocity, on the other hand, is related to the heat generated by plastic deformation. During the welding process, the slippage is the most pronounced on the front part of the tool shoulder. Also, it is higher on the retreating side than on the advancing side. Slip rate in the zone around the tool pin has very low values, almost negligible. In this zone, the heat generation from friction is very low, because the material is in paste-like state and subjected to intensive plastic deformation. The material flow velocity around the pin is higher in the zone around the root of the pin. In the radial direction, this quantity increases from the pin to the periphery of the tool shoulder.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - Influence of material velocity on heat generation during linear welding stage of friction stir welding
EP  - 1701
IS  - 5
SP  - 1693
VL  - 20
DO  - 10.2298/TSCI150904217M
ER  - 

@article{
author = "Murariu, Alin and Veljić, Darko and Barjaktarević, Dragana R. and Rakin, Marko and Radović, Nenad A. and Sedmak, Aleksandar and Djoković, Jelena M.",
year = "2016",
abstract = "The heat generated during friction stir welding process depends on plastic deformation of the material and friction between the tool and the material. In this work, heat generation is analysed with respect to the material velocity around the tool in Al alloy Al2024-T351 plate. The slip rate of the tool relative to the workpiece material is related to the frictional heat generated. The material velocity, on the other hand, is related to the heat generated by plastic deformation. During the welding process, the slippage is the most pronounced on the front part of the tool shoulder. Also, it is higher on the retreating side than on the advancing side. Slip rate in the zone around the tool pin has very low values, almost negligible. In this zone, the heat generation from friction is very low, because the material is in paste-like state and subjected to intensive plastic deformation. The material flow velocity around the pin is higher in the zone around the root of the pin. In the radial direction, this quantity increases from the pin to the periphery of the tool shoulder.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "Influence of material velocity on heat generation during linear welding stage of friction stir welding",
pages = "1701-1693",
number = "5",
volume = "20",
doi = "10.2298/TSCI150904217M"
}

Murariu, A., Veljić, D., Barjaktarević, D. R., Rakin, M., Radović, N. A., Sedmak, A.,& Djoković, J. M.. (2016). Influence of material velocity on heat generation during linear welding stage of friction stir welding. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 20(5), 1693-1701.
https://doi.org/10.2298/TSCI150904217M

Murariu A, Veljić D, Barjaktarević DR, Rakin M, Radović NA, Sedmak A, Djoković JM. Influence of material velocity on heat generation during linear welding stage of friction stir welding. in Thermal Science. 2016;20(5):1693-1701.
doi:10.2298/TSCI150904217M .

Murariu, Alin, Veljić, Darko, Barjaktarević, Dragana R., Rakin, Marko, Radović, Nenad A., Sedmak, Aleksandar, Djoković, Jelena M., "Influence of material velocity on heat generation during linear welding stage of friction stir welding" in Thermal Science, 20, no. 5 (2016):1693-1701,
https://doi.org/10.2298/TSCI150904217M . .

TY  - JOUR
AU  - Veljić, Darko
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
AU  - Radović, Nenad A.
AU  - Popović, N.
AU  - Dascau, Horia
AU  - Bajić, Nikola
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2169
AB  - In modern industrial production, every manufacturing and assembly process should be assessed with respect to its influence on the environment. For a company that invests in a new process, a careful analysis of HSE problems (Health, Safety and Environment) is very important. Friction stir welding (FSW) process offers numerous advantages regarding health protection, environmental effects and work safety in comparison with other welding procedures, such as arc welding. Arc welding produces a broad spec-trum of UV radiation, harmful for human health (skin, eyes). Exposure to this radiation without an adequate protection can lead to severe injuries. If appropriate protective measures are undertaken, the welder can easily be exposed to heat injuries. This is especially pronounced for arc welding of aluminium alloys, because high material conductivity of Al requires a high-energy arc, and also because its surface has more pronounced reflection than steel. This work deals with the FSW welding process and its advantages in comparison with arc welding processes with respect to health protection, environmental problems and work safety.
PB  - Institut za ispitivanje materijala, Beograd
T2  - Structural Integrity and Life
T1  - Advantages of friction stir welding over arc welding with respect to health and environmental protection and work safety [Prednosti zavarivanja trenjem sa mešanjem u odnosu na elektrolučno zavarivanje - Zaštita zdravlja i životne sredine i bezbednost na r
EP  - 116
IS  - 2
SP  - 111
VL  - 15
UR  - https://hdl.handle.net/21.15107/rcub_machinery_2169
ER  - 

@article{
author = "Veljić, Darko and Sedmak, Aleksandar and Rakin, Marko and Radović, Nenad A. and Popović, N. and Dascau, Horia and Bajić, Nikola",
year = "2015",
abstract = "In modern industrial production, every manufacturing and assembly process should be assessed with respect to its influence on the environment. For a company that invests in a new process, a careful analysis of HSE problems (Health, Safety and Environment) is very important. Friction stir welding (FSW) process offers numerous advantages regarding health protection, environmental effects and work safety in comparison with other welding procedures, such as arc welding. Arc welding produces a broad spec-trum of UV radiation, harmful for human health (skin, eyes). Exposure to this radiation without an adequate protection can lead to severe injuries. If appropriate protective measures are undertaken, the welder can easily be exposed to heat injuries. This is especially pronounced for arc welding of aluminium alloys, because high material conductivity of Al requires a high-energy arc, and also because its surface has more pronounced reflection than steel. This work deals with the FSW welding process and its advantages in comparison with arc welding processes with respect to health protection, environmental problems and work safety.",
publisher = "Institut za ispitivanje materijala, Beograd",
journal = "Structural Integrity and Life",
title = "Advantages of friction stir welding over arc welding with respect to health and environmental protection and work safety [Prednosti zavarivanja trenjem sa mešanjem u odnosu na elektrolučno zavarivanje - Zaštita zdravlja i životne sredine i bezbednost na r",
pages = "116-111",
number = "2",
volume = "15",
url = "https://hdl.handle.net/21.15107/rcub_machinery_2169"
}

Veljić, D., Sedmak, A., Rakin, M., Radović, N. A., Popović, N., Dascau, H.,& Bajić, N.. (2015). Advantages of friction stir welding over arc welding with respect to health and environmental protection and work safety [Prednosti zavarivanja trenjem sa mešanjem u odnosu na elektrolučno zavarivanje - Zaštita zdravlja i životne sredine i bezbednost na r. in Structural Integrity and Life
Institut za ispitivanje materijala, Beograd., 15(2), 111-116.
https://hdl.handle.net/21.15107/rcub_machinery_2169

Veljić D, Sedmak A, Rakin M, Radović NA, Popović N, Dascau H, Bajić N. Advantages of friction stir welding over arc welding with respect to health and environmental protection and work safety [Prednosti zavarivanja trenjem sa mešanjem u odnosu na elektrolučno zavarivanje - Zaštita zdravlja i životne sredine i bezbednost na r. in Structural Integrity and Life. 2015;15(2):111-116.
https://hdl.handle.net/21.15107/rcub_machinery_2169 .

Veljić, Darko, Sedmak, Aleksandar, Rakin, Marko, Radović, Nenad A., Popović, N., Dascau, Horia, Bajić, Nikola, "Advantages of friction stir welding over arc welding with respect to health and environmental protection and work safety [Prednosti zavarivanja trenjem sa mešanjem u odnosu na elektrolučno zavarivanje - Zaštita zdravlja i životne sredine i bezbednost na r" in Structural Integrity and Life, 15, no. 2 (2015):111-116,
https://hdl.handle.net/21.15107/rcub_machinery_2169 .

TY  - JOUR
AU  - Eramah, Abdsalam M.
AU  - Rakin, Marko
AU  - Veljić, Darko
AU  - Tadić, Srđan
AU  - Radović, Nenad A.
AU  - Zrilić, Milorad
AU  - Perović, Milenko M.
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2021
AB  - The aim of this work is to analyse the process of friction stir welding (FSW) of 3 mm thick aluminium plates made of high strength aluminium alloy - 2024 T3, as well as to assess the mechanical properties of the produced joints. Friction Stir Welding is a modern procedure which enables joining of similar and dissimilar materials in the solid state, by the combined action of heat and mechanical work. This paper presents an analysis of the experimental results obtained by testing the butt welded joints. Tensile strength of the produced joints is assessed, as well as the distribution of hardness, micro-and macrostructure through the joints (in the base material, nugget, heat affected zone and thermo-mechanically affected zone). Different combinations of the tool rotation speed and the welding speed are used, and the dependence of the properties of the joints on these parameters of welding technology is determined.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - Influence of friction stir welding parameters on properties of 2024 t3 aluminium alloy joints
EP  - S28
SP  - S21
VL  - 18
DO  - 10.2298/TSCI130307170E
ER  - 

@article{
author = "Eramah, Abdsalam M. and Rakin, Marko and Veljić, Darko and Tadić, Srđan and Radović, Nenad A. and Zrilić, Milorad and Perović, Milenko M.",
year = "2014",
abstract = "The aim of this work is to analyse the process of friction stir welding (FSW) of 3 mm thick aluminium plates made of high strength aluminium alloy - 2024 T3, as well as to assess the mechanical properties of the produced joints. Friction Stir Welding is a modern procedure which enables joining of similar and dissimilar materials in the solid state, by the combined action of heat and mechanical work. This paper presents an analysis of the experimental results obtained by testing the butt welded joints. Tensile strength of the produced joints is assessed, as well as the distribution of hardness, micro-and macrostructure through the joints (in the base material, nugget, heat affected zone and thermo-mechanically affected zone). Different combinations of the tool rotation speed and the welding speed are used, and the dependence of the properties of the joints on these parameters of welding technology is determined.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "Influence of friction stir welding parameters on properties of 2024 t3 aluminium alloy joints",
pages = "S28-S21",
volume = "18",
doi = "10.2298/TSCI130307170E"
}

Eramah, A. M., Rakin, M., Veljić, D., Tadić, S., Radović, N. A., Zrilić, M.,& Perović, M. M.. (2014). Influence of friction stir welding parameters on properties of 2024 t3 aluminium alloy joints. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 18, S21-S28.
https://doi.org/10.2298/TSCI130307170E

Eramah AM, Rakin M, Veljić D, Tadić S, Radović NA, Zrilić M, Perović MM. Influence of friction stir welding parameters on properties of 2024 t3 aluminium alloy joints. in Thermal Science. 2014;18:S21-S28.
doi:10.2298/TSCI130307170E .

Eramah, Abdsalam M., Rakin, Marko, Veljić, Darko, Tadić, Srđan, Radović, Nenad A., Zrilić, Milorad, Perović, Milenko M., "Influence of friction stir welding parameters on properties of 2024 t3 aluminium alloy joints" in Thermal Science, 18 (2014):S21-S28,
https://doi.org/10.2298/TSCI130307170E . .

TY  - JOUR
AU  - Veljić, Darko
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
AU  - Bajić, Nikola
AU  - Međo, Bojan
AU  - Bajić, Darko
AU  - Grabulov, Vencislav
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1865
AB  - This paper presents experimental and numerical analysis of the change of temperature and force in the vertical direction during the friction stir welding of high-strength aluminium alloy 2024 T3. This procedure confirmed the correctness of the numerical model, which is subsequently used for analysis of the temperature field in the welding zone, where it is different to determine the temperature experimentally. 3D finite element model is developed using the software package Abaqus; arbitrary Lagrangian-Eulerian formulation is applied. Johnson-Cook material law and Coulomb's Law of friction are used for modelling the material behaviour. Temperature fields are symmetrical with respect to the welding line. The temperature values below the tool shoulder, i.e. in the welding zone, which are reached during the plunge stage, are approximately constant during the entire welding process and lie within the interval 430-502 degrees C. The temperature of the material in the vicinity of the tool is about 500 degrees C, while the values on the top surface of the welding plates (outside the welding zone, but close to the tool shoulder) are about 400 degrees C. The temperature difference between the top and bottom surface of the plates is small, 10-15 degrees C.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - Experimental and numerical thermo - mechanical analysis of friction stir welding of high - strength alluminium alloy
EP  - S38
SP  - S29
VL  - 18
DO  - 10.2298/TSCI130512171V
ER  - 

@article{
author = "Veljić, Darko and Sedmak, Aleksandar and Rakin, Marko and Bajić, Nikola and Međo, Bojan and Bajić, Darko and Grabulov, Vencislav",
year = "2014",
abstract = "This paper presents experimental and numerical analysis of the change of temperature and force in the vertical direction during the friction stir welding of high-strength aluminium alloy 2024 T3. This procedure confirmed the correctness of the numerical model, which is subsequently used for analysis of the temperature field in the welding zone, where it is different to determine the temperature experimentally. 3D finite element model is developed using the software package Abaqus; arbitrary Lagrangian-Eulerian formulation is applied. Johnson-Cook material law and Coulomb's Law of friction are used for modelling the material behaviour. Temperature fields are symmetrical with respect to the welding line. The temperature values below the tool shoulder, i.e. in the welding zone, which are reached during the plunge stage, are approximately constant during the entire welding process and lie within the interval 430-502 degrees C. The temperature of the material in the vicinity of the tool is about 500 degrees C, while the values on the top surface of the welding plates (outside the welding zone, but close to the tool shoulder) are about 400 degrees C. The temperature difference between the top and bottom surface of the plates is small, 10-15 degrees C.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "Experimental and numerical thermo - mechanical analysis of friction stir welding of high - strength alluminium alloy",
pages = "S38-S29",
volume = "18",
doi = "10.2298/TSCI130512171V"
}

Veljić, D., Sedmak, A., Rakin, M., Bajić, N., Međo, B., Bajić, D.,& Grabulov, V.. (2014). Experimental and numerical thermo - mechanical analysis of friction stir welding of high - strength alluminium alloy. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 18, S29-S38.
https://doi.org/10.2298/TSCI130512171V

Veljić D, Sedmak A, Rakin M, Bajić N, Međo B, Bajić D, Grabulov V. Experimental and numerical thermo - mechanical analysis of friction stir welding of high - strength alluminium alloy. in Thermal Science. 2014;18:S29-S38.
doi:10.2298/TSCI130512171V .

Veljić, Darko, Sedmak, Aleksandar, Rakin, Marko, Bajić, Nikola, Međo, Bojan, Bajić, Darko, Grabulov, Vencislav, "Experimental and numerical thermo - mechanical analysis of friction stir welding of high - strength alluminium alloy" in Thermal Science, 18 (2014):S29-S38,
https://doi.org/10.2298/TSCI130512171V . .

TY  - JOUR
AU  - Veljić, Darko
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
AU  - Radović, Nenad A.
AU  - Bajić, Nikola
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1613
AB  - Cilj rada je analiza promene vertikalne sile i temperature tokom procesa zavarivanja trenjem mešanjem (FSW) legura aluminijuma visoke čvrstoće (2024 T3). FSW postupak je složen nelinearan proces praćen velikim plastičnim deformacijama, visokim temperaturama i plastičnim tečenjem materijala u zoni zavarivanja. To je postupak spajanja materijala u tzv. čvrstoj fazi, kombinovanim delovanjem toplote i mehaničkog rada. Analiza promene sile i temperature tokom procesa zavarivanja omogućava bolje razumevanje i kontrolu samog procesa. U radu je analizirana i praćena promena sile u vertikalnom pravcu pomoću dinamometra i promena temperature na gornjoj površini radne ploče u blizini čela valjka alata pomoću termovizijske kamere.
AB  - The aim of this paper is to analyze changes of vertical force and temperature during friction stir welding process of high strength aluminum alloys (2024 T3). FSW process is a complex nonlinear process accompanied by large plastic deformation, high temperatures and plastic material flow in the welding zone. It is the procedure of material connecting in the so-called solid phase, through the combined action of heat and mechanical work. Analysis of force and temperature changes during the process of welding allows better understanding and control of the process. This paper analyzes the change of force in the vertical direction using a dynamometer and temperature changes on the upper surface of the working panel near the tops of the roller tool using thermal imaging cameras.
PB  - DUZS - Društvo za unapređivanje zavarivanja u Srbiji, Beograd
T2  - Zavarivanje i zavarene konstrukcije
T1  - Promena temperature i vertikalne sile tokom procesa zavarivanja trenjem mešanjem
T1  - Change of temperature and vertical force during friction stir welding
EP  - 59
IS  - 2
SP  - 53
VL  - 58
UR  - https://hdl.handle.net/21.15107/rcub_machinery_1613
ER  - 

@article{
author = "Veljić, Darko and Sedmak, Aleksandar and Rakin, Marko and Radović, Nenad A. and Bajić, Nikola",
year = "2013",
abstract = "Cilj rada je analiza promene vertikalne sile i temperature tokom procesa zavarivanja trenjem mešanjem (FSW) legura aluminijuma visoke čvrstoće (2024 T3). FSW postupak je složen nelinearan proces praćen velikim plastičnim deformacijama, visokim temperaturama i plastičnim tečenjem materijala u zoni zavarivanja. To je postupak spajanja materijala u tzv. čvrstoj fazi, kombinovanim delovanjem toplote i mehaničkog rada. Analiza promene sile i temperature tokom procesa zavarivanja omogućava bolje razumevanje i kontrolu samog procesa. U radu je analizirana i praćena promena sile u vertikalnom pravcu pomoću dinamometra i promena temperature na gornjoj površini radne ploče u blizini čela valjka alata pomoću termovizijske kamere., The aim of this paper is to analyze changes of vertical force and temperature during friction stir welding process of high strength aluminum alloys (2024 T3). FSW process is a complex nonlinear process accompanied by large plastic deformation, high temperatures and plastic material flow in the welding zone. It is the procedure of material connecting in the so-called solid phase, through the combined action of heat and mechanical work. Analysis of force and temperature changes during the process of welding allows better understanding and control of the process. This paper analyzes the change of force in the vertical direction using a dynamometer and temperature changes on the upper surface of the working panel near the tops of the roller tool using thermal imaging cameras.",
publisher = "DUZS - Društvo za unapređivanje zavarivanja u Srbiji, Beograd",
journal = "Zavarivanje i zavarene konstrukcije",
title = "Promena temperature i vertikalne sile tokom procesa zavarivanja trenjem mešanjem, Change of temperature and vertical force during friction stir welding",
pages = "59-53",
number = "2",
volume = "58",
url = "https://hdl.handle.net/21.15107/rcub_machinery_1613"
}

Veljić, D., Sedmak, A., Rakin, M., Radović, N. A.,& Bajić, N.. (2013). Promena temperature i vertikalne sile tokom procesa zavarivanja trenjem mešanjem. in Zavarivanje i zavarene konstrukcije
DUZS - Društvo za unapređivanje zavarivanja u Srbiji, Beograd., 58(2), 53-59.
https://hdl.handle.net/21.15107/rcub_machinery_1613

Veljić D, Sedmak A, Rakin M, Radović NA, Bajić N. Promena temperature i vertikalne sile tokom procesa zavarivanja trenjem mešanjem. in Zavarivanje i zavarene konstrukcije. 2013;58(2):53-59.
https://hdl.handle.net/21.15107/rcub_machinery_1613 .

Veljić, Darko, Sedmak, Aleksandar, Rakin, Marko, Radović, Nenad A., Bajić, Nikola, "Promena temperature i vertikalne sile tokom procesa zavarivanja trenjem mešanjem" in Zavarivanje i zavarene konstrukcije, 58, no. 2 (2013):53-59,
https://hdl.handle.net/21.15107/rcub_machinery_1613 .

TY  - JOUR
AU  - Veljić, Darko
AU  - Rakin, Marko
AU  - Perović, Milenko M.
AU  - Međo, Bojan
AU  - Radaković, Zoran
AU  - Todorović, Petar
AU  - Pavišić, Mirko N.
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1666
AB  - This paper deals with the heat generation in the Al alloy Al2024-T3 plate under different rotating speeds and plunge speeds during the plunge stage of friction stir welding. A 3-D finite element model is developed in the commercial code ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson- Cook material law, and Coulomb’s Law of friction. The heat generation in friction stir welding can be divided into two parts: frictional heat generated by the tool and heat generated by material deformation near the pin and the tool shoulder region. Numerical results obtained in this work indicate a more prominent influence from the friction-generated heat. The slip rate of the tool relative to the workpiece material is related to this portion of heat. The material velocity, on the other hand, is related to the heat generated by plastic deformation. Increasing the plunging speed of the tool decreases the friction-generated heat and increases the amount of deformation-generated heat, while increasing the tool rotating speed has the opposite influence on both heat portions. Numerical results are compared with the experimental ones, in order to validate the numerical model, and a good agreement is obtained.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - Heat generation during plunge stage in friction stir welding
EP  - 496
IS  - 2
SP  - 489
VL  - 17
DO  - 10.2298/TSCI120301205V
ER  - 

@article{
author = "Veljić, Darko and Rakin, Marko and Perović, Milenko M. and Međo, Bojan and Radaković, Zoran and Todorović, Petar and Pavišić, Mirko N.",
year = "2013",
abstract = "This paper deals with the heat generation in the Al alloy Al2024-T3 plate under different rotating speeds and plunge speeds during the plunge stage of friction stir welding. A 3-D finite element model is developed in the commercial code ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson- Cook material law, and Coulomb’s Law of friction. The heat generation in friction stir welding can be divided into two parts: frictional heat generated by the tool and heat generated by material deformation near the pin and the tool shoulder region. Numerical results obtained in this work indicate a more prominent influence from the friction-generated heat. The slip rate of the tool relative to the workpiece material is related to this portion of heat. The material velocity, on the other hand, is related to the heat generated by plastic deformation. Increasing the plunging speed of the tool decreases the friction-generated heat and increases the amount of deformation-generated heat, while increasing the tool rotating speed has the opposite influence on both heat portions. Numerical results are compared with the experimental ones, in order to validate the numerical model, and a good agreement is obtained.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "Heat generation during plunge stage in friction stir welding",
pages = "496-489",
number = "2",
volume = "17",
doi = "10.2298/TSCI120301205V"
}

Veljić, D., Rakin, M., Perović, M. M., Međo, B., Radaković, Z., Todorović, P.,& Pavišić, M. N.. (2013). Heat generation during plunge stage in friction stir welding. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 17(2), 489-496.
https://doi.org/10.2298/TSCI120301205V

Veljić D, Rakin M, Perović MM, Međo B, Radaković Z, Todorović P, Pavišić MN. Heat generation during plunge stage in friction stir welding. in Thermal Science. 2013;17(2):489-496.
doi:10.2298/TSCI120301205V .

Veljić, Darko, Rakin, Marko, Perović, Milenko M., Međo, Bojan, Radaković, Zoran, Todorović, Petar, Pavišić, Mirko N., "Heat generation during plunge stage in friction stir welding" in Thermal Science, 17, no. 2 (2013):489-496,
https://doi.org/10.2298/TSCI120301205V . .

TY  - JOUR
AU  - Perović, Milenko M.
AU  - Veljić, Darko
AU  - Rakin, Marko
AU  - Radović, Nenad A.
AU  - Sedmak, Aleksandar
AU  - Bajić, Nikola
PY  - 2012
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1606
AB  - This paper defines a set of welding parameters for the Friction-Stir Welding (FSW) of two forged panels of the alloy EN AW 7049A in a T652 temper and discusses the plunge stage of FSW using numerical modeling. This multi-component aluminum alloy is characterized by high strength, reduced plasticity and poor weldability. Observations of the macrostructure and microstructure clearly showed typical zones of a FSW joint and the appropriate grain sizes. The finest grains were observed within the nugget, while the coarsest grains are found to be in the HAZ. The ultimate tensile strength is 80.3 % of the parent material. A coupled thermo-mechanical model was developed to study the temperature fields and the plunge force of the alloy EN AW 7049A under different rotating speeds, (300, 400 and 500) r/min, during the FSW process of the plunge stage. A three-dimensional FE model has been developed in ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and Coulomb's Law of Friction. Numerical results indicate that the maximum temperature in the FSW process can be increased with an increase in the rotational speed, which can be used to reduce the plunge force.
PB  - Institute of Metals and Technology
T2  - Materiali in Tehnologije
T1  - Friction-stir welding of high-strength aluminium alloys and a numerical simulation of the plunge stage
EP  - 221
IS  - 3
SP  - 215
VL  - 46
UR  - https://hdl.handle.net/21.15107/rcub_technorep_2012
ER  - 

@article{
author = "Perović, Milenko M. and Veljić, Darko and Rakin, Marko and Radović, Nenad A. and Sedmak, Aleksandar and Bajić, Nikola",
year = "2012",
abstract = "This paper defines a set of welding parameters for the Friction-Stir Welding (FSW) of two forged panels of the alloy EN AW 7049A in a T652 temper and discusses the plunge stage of FSW using numerical modeling. This multi-component aluminum alloy is characterized by high strength, reduced plasticity and poor weldability. Observations of the macrostructure and microstructure clearly showed typical zones of a FSW joint and the appropriate grain sizes. The finest grains were observed within the nugget, while the coarsest grains are found to be in the HAZ. The ultimate tensile strength is 80.3 % of the parent material. A coupled thermo-mechanical model was developed to study the temperature fields and the plunge force of the alloy EN AW 7049A under different rotating speeds, (300, 400 and 500) r/min, during the FSW process of the plunge stage. A three-dimensional FE model has been developed in ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and Coulomb's Law of Friction. Numerical results indicate that the maximum temperature in the FSW process can be increased with an increase in the rotational speed, which can be used to reduce the plunge force.",
publisher = "Institute of Metals and Technology",
journal = "Materiali in Tehnologije",
title = "Friction-stir welding of high-strength aluminium alloys and a numerical simulation of the plunge stage",
pages = "221-215",
number = "3",
volume = "46",
url = "https://hdl.handle.net/21.15107/rcub_technorep_2012"
}

Perović, M. M., Veljić, D., Rakin, M., Radović, N. A., Sedmak, A.,& Bajić, N.. (2012). Friction-stir welding of high-strength aluminium alloys and a numerical simulation of the plunge stage. in Materiali in Tehnologije
Institute of Metals and Technology., 46(3), 215-221.
https://hdl.handle.net/21.15107/rcub_technorep_2012

Perović MM, Veljić D, Rakin M, Radović NA, Sedmak A, Bajić N. Friction-stir welding of high-strength aluminium alloys and a numerical simulation of the plunge stage. in Materiali in Tehnologije. 2012;46(3):215-221.
https://hdl.handle.net/21.15107/rcub_technorep_2012 .

Perović, Milenko M., Veljić, Darko, Rakin, Marko, Radović, Nenad A., Sedmak, Aleksandar, Bajić, Nikola, "Friction-stir welding of high-strength aluminium alloys and a numerical simulation of the plunge stage" in Materiali in Tehnologije, 46, no. 3 (2012):215-221,
https://hdl.handle.net/21.15107/rcub_technorep_2012 .

TY  - JOUR
AU  - Veljić, Darko
AU  - Perović, Milenko M.
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
AU  - Trifunović, Miroslav V.
AU  - Bajić, Nikola
AU  - Bajić, Darko
PY  - 2012
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1394
AB  - A coupled thermo-mechanical model was developed to study the temperature fields, the plunge force and the plastic deformations of Al alloy 2024-T351 under different rotating speed: 350, 400, and 450 rpm, during the friction stir welding process. 3-D FE model has been developed in ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law, and the Coulomb’s Law of friction. Numerical results indicate that the maximum temperature in the friction stir welding process is lower than the melting point of the welding material. The temperature filed is approximately symmetrical along the welding line. A lower plastic strain region can be found near the welding tool in the trailing side on the bottom surface. With increasing rotation speed, the low plastic strain region is reduced. When the rotational speed is increased, the plunge force can be reduced. Regions with high equivalent plastic strains are observed which correspond to the nugget and the flow arm.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - A coupled thermo-mechanical model of friction stir welding
EP  - 534
IS  - 2
SP  - 527
VL  - 16
DO  - 10.2298/TSCI110729012V
ER  - 

@article{
author = "Veljić, Darko and Perović, Milenko M. and Sedmak, Aleksandar and Rakin, Marko and Trifunović, Miroslav V. and Bajić, Nikola and Bajić, Darko",
year = "2012",
abstract = "A coupled thermo-mechanical model was developed to study the temperature fields, the plunge force and the plastic deformations of Al alloy 2024-T351 under different rotating speed: 350, 400, and 450 rpm, during the friction stir welding process. 3-D FE model has been developed in ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law, and the Coulomb’s Law of friction. Numerical results indicate that the maximum temperature in the friction stir welding process is lower than the melting point of the welding material. The temperature filed is approximately symmetrical along the welding line. A lower plastic strain region can be found near the welding tool in the trailing side on the bottom surface. With increasing rotation speed, the low plastic strain region is reduced. When the rotational speed is increased, the plunge force can be reduced. Regions with high equivalent plastic strains are observed which correspond to the nugget and the flow arm.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "A coupled thermo-mechanical model of friction stir welding",
pages = "534-527",
number = "2",
volume = "16",
doi = "10.2298/TSCI110729012V"
}

Veljić, D., Perović, M. M., Sedmak, A., Rakin, M., Trifunović, M. V., Bajić, N.,& Bajić, D.. (2012). A coupled thermo-mechanical model of friction stir welding. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 16(2), 527-534.
https://doi.org/10.2298/TSCI110729012V

Veljić D, Perović MM, Sedmak A, Rakin M, Trifunović MV, Bajić N, Bajić D. A coupled thermo-mechanical model of friction stir welding. in Thermal Science. 2012;16(2):527-534.
doi:10.2298/TSCI110729012V .

Veljić, Darko, Perović, Milenko M., Sedmak, Aleksandar, Rakin, Marko, Trifunović, Miroslav V., Bajić, Nikola, Bajić, Darko, "A coupled thermo-mechanical model of friction stir welding" in Thermal Science, 16, no. 2 (2012):527-534,
https://doi.org/10.2298/TSCI110729012V . .

TY  - JOUR
AU  - Veljić, Darko
AU  - Perović, Milenko M.
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
AU  - Bajić, Nikola
AU  - Međo, Bojan
AU  - Dascau, Horia
PY  - 2011
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1282
AB  - U ovom radu je istražena faza uranjanja alata primenom numeričkog modeliranja. Trodimenzionalni model konačnih elemenata (FEM) faze uranjanja je razvijen primenom softvera ABAQUS radi proučavanja termomehaničkih procesa koji se odvijaju tokom faze uranjanja. Spregnuti termomehanički 3D FE model se bazira na proizvoljnim formulacijama Lagranža-Ojlera, zakonu materijala Džonson-Kuk i Kulonovom zakonu trenja. Model je razvijen radi proučavanja temperaturskih polja legure Al2024-T351 pod različitim parametrima postupka (brzina rotacije) kod postupka zavarivanja trenjem mešanjem (FSW). Numerički rezultati pokazuju da se maksimalna temperatura postupka FSW može povećati sa povećanjem brzine rotacije, kao i da je temperatura niža od tačke topljenja zavarenog materijala. U ovoj analizi, temperatura, pomeranje i mehanički odzivi se određuju simultano. Izdvajanje toplote kod FSW se može podeliti na tri dela: toplota trenja koja se razvija kretanjem čela alata, toplota trenja dobijena kretanjem trna alata, kao i toplota usled plastične deformacije materijala u blizini oblasti trna alata.
AB  - This paper investigates the plunge stage using numerical modeling. A three-dimensional finite element model (FEM) of the plunge stage is developed using the commercial code ABAQUS to study the thermo-mechanical processes involved during the plunge stage. A coupled thermo-mechanical 3D FE model uses the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and Coulomb's Law of friction. The model is developed to study the temperature fields of alloy Al2024-T351 under different process parameters (rotating speed) during the friction stir welding (FSW) process. Numerical results indicate that the maximal temperature of the FSW process can be increased with the increase of rotational speed and that temperature is lower than the melting point of the welding material. In this analysis, temperature, displacement, and mechanical responses are determined simultaneously. The heat generation in FSW can be divided into three parts: frictional heat generated by the tool shoulder, frictional heat generated by the tool pin, and heat generated by material deformation near the pin region.
PB  - Institut za ispitivanje materijala, Beograd
T2  - Structural Integrity and Life
T1  - Numerička simulacija faze uranjanja kod zavarivanja trenjem mešanjem
T1  - Numerical simulation of the plunge stage in friction stir welding
EP  - 134
IS  - 2
SP  - 131
VL  - 11
UR  - https://hdl.handle.net/21.15107/rcub_machinery_1282
ER  - 

@article{
author = "Veljić, Darko and Perović, Milenko M. and Sedmak, Aleksandar and Rakin, Marko and Bajić, Nikola and Međo, Bojan and Dascau, Horia",
year = "2011",
abstract = "U ovom radu je istražena faza uranjanja alata primenom numeričkog modeliranja. Trodimenzionalni model konačnih elemenata (FEM) faze uranjanja je razvijen primenom softvera ABAQUS radi proučavanja termomehaničkih procesa koji se odvijaju tokom faze uranjanja. Spregnuti termomehanički 3D FE model se bazira na proizvoljnim formulacijama Lagranža-Ojlera, zakonu materijala Džonson-Kuk i Kulonovom zakonu trenja. Model je razvijen radi proučavanja temperaturskih polja legure Al2024-T351 pod različitim parametrima postupka (brzina rotacije) kod postupka zavarivanja trenjem mešanjem (FSW). Numerički rezultati pokazuju da se maksimalna temperatura postupka FSW može povećati sa povećanjem brzine rotacije, kao i da je temperatura niža od tačke topljenja zavarenog materijala. U ovoj analizi, temperatura, pomeranje i mehanički odzivi se određuju simultano. Izdvajanje toplote kod FSW se može podeliti na tri dela: toplota trenja koja se razvija kretanjem čela alata, toplota trenja dobijena kretanjem trna alata, kao i toplota usled plastične deformacije materijala u blizini oblasti trna alata., This paper investigates the plunge stage using numerical modeling. A three-dimensional finite element model (FEM) of the plunge stage is developed using the commercial code ABAQUS to study the thermo-mechanical processes involved during the plunge stage. A coupled thermo-mechanical 3D FE model uses the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and Coulomb's Law of friction. The model is developed to study the temperature fields of alloy Al2024-T351 under different process parameters (rotating speed) during the friction stir welding (FSW) process. Numerical results indicate that the maximal temperature of the FSW process can be increased with the increase of rotational speed and that temperature is lower than the melting point of the welding material. In this analysis, temperature, displacement, and mechanical responses are determined simultaneously. The heat generation in FSW can be divided into three parts: frictional heat generated by the tool shoulder, frictional heat generated by the tool pin, and heat generated by material deformation near the pin region.",
publisher = "Institut za ispitivanje materijala, Beograd",
journal = "Structural Integrity and Life",
title = "Numerička simulacija faze uranjanja kod zavarivanja trenjem mešanjem, Numerical simulation of the plunge stage in friction stir welding",
pages = "134-131",
number = "2",
volume = "11",
url = "https://hdl.handle.net/21.15107/rcub_machinery_1282"
}

Veljić, D., Perović, M. M., Sedmak, A., Rakin, M., Bajić, N., Međo, B.,& Dascau, H.. (2011). Numerička simulacija faze uranjanja kod zavarivanja trenjem mešanjem. in Structural Integrity and Life
Institut za ispitivanje materijala, Beograd., 11(2), 131-134.
https://hdl.handle.net/21.15107/rcub_machinery_1282

Veljić D, Perović MM, Sedmak A, Rakin M, Bajić N, Međo B, Dascau H. Numerička simulacija faze uranjanja kod zavarivanja trenjem mešanjem. in Structural Integrity and Life. 2011;11(2):131-134.
https://hdl.handle.net/21.15107/rcub_machinery_1282 .

Veljić, Darko, Perović, Milenko M., Sedmak, Aleksandar, Rakin, Marko, Bajić, Nikola, Međo, Bojan, Dascau, Horia, "Numerička simulacija faze uranjanja kod zavarivanja trenjem mešanjem" in Structural Integrity and Life, 11, no. 2 (2011):131-134,
https://hdl.handle.net/21.15107/rcub_machinery_1282 .

TY  - JOUR
AU  - Veljić, Darko
AU  - Perović, Milenko M.
AU  - Sedmak, Aleksandar
AU  - Rakin, Marko
PY  - 2011
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1259
AB  - Tema ovog rada je proučavanje faze probijanja korišćenjem numeričkog modela. Analizirana je promena temperature i sile probijanja u toku faze probijanja postupka zavarivanja trenjem mešanjem za legure aluminijuma visoke čvrstoće EN AW 2024 T 351 i EN AW 7049A T 652, pri različitim brzinama rotacije alata. Numerički rezultati pokazuju da maksimalne temperature u postupku zavarivanja trenjem mešanjem mogu biti povećane sa povećanjem brzine rotacije alata i da su temperature manje od temperature topljenja materijala koji se zavaruje. Pri istim brzinama rotacije alata, registrovana je veća temperatura kod legure aluminijuma EN AW 2024 T 351 i veća sila probijanja - otpor materijala kod legure EN AW 7049A T 652. Sa povećanjem brzine rotacije alata, sila probijanja može biti smanjena. Trodimenzionalni model konačnih elemenata faze probijanja je razvijen korišćenjem ABAQUS programskog paketa za proučavanje termomehaničkih procesa faze probijanja. Spregnuti termo-mehanički model konačnih elemenata koristi proizvoljnu Lagranž-Ojlerovu formulaciju, Džonson-Kukov zakon i Kulonov zakon trenja. U ovoj analizi se temperatura, pomjeranje i mehaničke reakcije posmatraju istovremeno. Generisanje toplote u postupku zavarivanja trenjem mešanjem se može podeliti na tri dela:generisanje toplote trenjem od čela alata, generisanje toplote trenjem od trna alata i generisanje toplote od plastičnih deformacija u blizini trna alata.
AB  - This paper investigates the plunge stage using numerical modeling. Change of temperature and plunge force have been analyzed during the plunge stage of the FSW procedure for high hardness aluminum alloys EN AW 2024 T 351 and EN AW 7049A T 652, at different speed of tool rotation. Numerical results indicate that the maximum temperature in the FSW process can be increased with the increase of the rotational speed and that temperature is lower than the melting point of the welding material. Higher temperature was registered at the aluminum alloy EN AW 2024 T 351 at the same speed of tool rotation, and higher plunge force - resistance of material was registered at the alloy EN AW 7049A T 652. When the rotational speed is increased, the plunge force can be reduced. A three-dimensional finite element model (FEM) of the plunge stage was developed using the commercial code ABAQUS to study the thermo-mechanical processes involved during the plunge stage. A coupled thermo-mechanical 3D FE model using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and the Coulomb's Law of friction. In this analysis, temperature, displacement and mechanical responses are determined simultaneously. The heat generation in FSW can be divided into three parts: frictional heat generated by the tool shoulder, frictional heat generated by the tool pin, and heat generated by material plastic deformation near the pin region.
PB  - Univerzitet u Novom Sadu - Fakultet tehničkih nauka - Institut za proizvodno mašinstvo, Novi Sad
T2  - Journal for Technology of Plasticity
T1  - Numerička simulacija faze probijanja postupka zavarivanja trenjem mešanjem legura EN AW 2024 T 351 i EN AW 7049A T 652
T1  - Numerical simulation of the plunge stage in friction stir welding alloys EN AW 2024 T 351 and EN AW 7049A T 652
EP  - 110
IS  - 2
SP  - 97
VL  - 36
UR  - https://hdl.handle.net/21.15107/rcub_technorep_1787
ER  - 

@article{
author = "Veljić, Darko and Perović, Milenko M. and Sedmak, Aleksandar and Rakin, Marko",
year = "2011",
abstract = "Tema ovog rada je proučavanje faze probijanja korišćenjem numeričkog modela. Analizirana je promena temperature i sile probijanja u toku faze probijanja postupka zavarivanja trenjem mešanjem za legure aluminijuma visoke čvrstoće EN AW 2024 T 351 i EN AW 7049A T 652, pri različitim brzinama rotacije alata. Numerički rezultati pokazuju da maksimalne temperature u postupku zavarivanja trenjem mešanjem mogu biti povećane sa povećanjem brzine rotacije alata i da su temperature manje od temperature topljenja materijala koji se zavaruje. Pri istim brzinama rotacije alata, registrovana je veća temperatura kod legure aluminijuma EN AW 2024 T 351 i veća sila probijanja - otpor materijala kod legure EN AW 7049A T 652. Sa povećanjem brzine rotacije alata, sila probijanja može biti smanjena. Trodimenzionalni model konačnih elemenata faze probijanja je razvijen korišćenjem ABAQUS programskog paketa za proučavanje termomehaničkih procesa faze probijanja. Spregnuti termo-mehanički model konačnih elemenata koristi proizvoljnu Lagranž-Ojlerovu formulaciju, Džonson-Kukov zakon i Kulonov zakon trenja. U ovoj analizi se temperatura, pomjeranje i mehaničke reakcije posmatraju istovremeno. Generisanje toplote u postupku zavarivanja trenjem mešanjem se može podeliti na tri dela:generisanje toplote trenjem od čela alata, generisanje toplote trenjem od trna alata i generisanje toplote od plastičnih deformacija u blizini trna alata., This paper investigates the plunge stage using numerical modeling. Change of temperature and plunge force have been analyzed during the plunge stage of the FSW procedure for high hardness aluminum alloys EN AW 2024 T 351 and EN AW 7049A T 652, at different speed of tool rotation. Numerical results indicate that the maximum temperature in the FSW process can be increased with the increase of the rotational speed and that temperature is lower than the melting point of the welding material. Higher temperature was registered at the aluminum alloy EN AW 2024 T 351 at the same speed of tool rotation, and higher plunge force - resistance of material was registered at the alloy EN AW 7049A T 652. When the rotational speed is increased, the plunge force can be reduced. A three-dimensional finite element model (FEM) of the plunge stage was developed using the commercial code ABAQUS to study the thermo-mechanical processes involved during the plunge stage. A coupled thermo-mechanical 3D FE model using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and the Coulomb's Law of friction. In this analysis, temperature, displacement and mechanical responses are determined simultaneously. The heat generation in FSW can be divided into three parts: frictional heat generated by the tool shoulder, frictional heat generated by the tool pin, and heat generated by material plastic deformation near the pin region.",
publisher = "Univerzitet u Novom Sadu - Fakultet tehničkih nauka - Institut za proizvodno mašinstvo, Novi Sad",
journal = "Journal for Technology of Plasticity",
title = "Numerička simulacija faze probijanja postupka zavarivanja trenjem mešanjem legura EN AW 2024 T 351 i EN AW 7049A T 652, Numerical simulation of the plunge stage in friction stir welding alloys EN AW 2024 T 351 and EN AW 7049A T 652",
pages = "110-97",
number = "2",
volume = "36",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1787"
}

Veljić, D., Perović, M. M., Sedmak, A.,& Rakin, M.. (2011). Numerička simulacija faze probijanja postupka zavarivanja trenjem mešanjem legura EN AW 2024 T 351 i EN AW 7049A T 652. in Journal for Technology of Plasticity
Univerzitet u Novom Sadu - Fakultet tehničkih nauka - Institut za proizvodno mašinstvo, Novi Sad., 36(2), 97-110.
https://hdl.handle.net/21.15107/rcub_technorep_1787

Veljić D, Perović MM, Sedmak A, Rakin M. Numerička simulacija faze probijanja postupka zavarivanja trenjem mešanjem legura EN AW 2024 T 351 i EN AW 7049A T 652. in Journal for Technology of Plasticity. 2011;36(2):97-110.
https://hdl.handle.net/21.15107/rcub_technorep_1787 .

Veljić, Darko, Perović, Milenko M., Sedmak, Aleksandar, Rakin, Marko, "Numerička simulacija faze probijanja postupka zavarivanja trenjem mešanjem legura EN AW 2024 T 351 i EN AW 7049A T 652" in Journal for Technology of Plasticity, 36, no. 2 (2011):97-110,
https://hdl.handle.net/21.15107/rcub_technorep_1787 .

TY  - JOUR
AU  - Veljić, Darko
AU  - Radović, Nenad A.
AU  - Sedmak, Aleksandar
AU  - Perović, Milenko M.
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1049
AB  - Cilj rada je osvajanje tehnologije zavarivanja aluminijumskih legura postupkom zavarivanja trenjem alatom (FSW). Zavarivanje trenjem alatom predstavlja jedan od najsavremenijih postupaka, sa velikom perspektivom dalje primene, pošto pruža najraznovrsnije mogućnosti za zavarivanje raznorodnih materijala. U radu su analizirani eksperimentalni rezultati su čeono zavarenih spojeva aluminijumskih ploča zavarenih postupkom zavarivanja trenjem alatom. Izvršeno je poređenje raspodele tvrdoće u zavarenom spoju u zavisnosti od parametara zavarivanja odnosno količine unete toplote u zoni zavarivanja, debljine ploča i tipa aluminijumske legure.
AB  - The objective of this paper is a development of welding technology of aluminium alloys by Friction Stir Welding (FSW). FSW is a very modern welding process with a great future use, primarily due to a variety of possible combinations of dissimilar materials to be welded. In this paper experimental results of butt welds for the friction stir welding of aluminium alloys are analyzed. A comparison hardness distribution in the welds was done considering welding parameters, that is the quantity of heat in the welding zone, panels thickness and aluminum alloy type.
PB  - DUZS - Društvo za unapređivanje zavarivanja u Srbiji, Beograd
T2  - Zavarivanje i zavarene konstrukcije
T1  - Tehnologija zavarivanja aluminijumskih legura postupkom zavarivanja trenjem alatom
T1  - Welding technology of aluminium alloys using friction stir welding
EP  - 20
IS  - 1
SP  - 13
VL  - 55
UR  - https://hdl.handle.net/21.15107/rcub_technorep_1647
ER  - 

@article{
author = "Veljić, Darko and Radović, Nenad A. and Sedmak, Aleksandar and Perović, Milenko M.",
year = "2010",
abstract = "Cilj rada je osvajanje tehnologije zavarivanja aluminijumskih legura postupkom zavarivanja trenjem alatom (FSW). Zavarivanje trenjem alatom predstavlja jedan od najsavremenijih postupaka, sa velikom perspektivom dalje primene, pošto pruža najraznovrsnije mogućnosti za zavarivanje raznorodnih materijala. U radu su analizirani eksperimentalni rezultati su čeono zavarenih spojeva aluminijumskih ploča zavarenih postupkom zavarivanja trenjem alatom. Izvršeno je poređenje raspodele tvrdoće u zavarenom spoju u zavisnosti od parametara zavarivanja odnosno količine unete toplote u zoni zavarivanja, debljine ploča i tipa aluminijumske legure., The objective of this paper is a development of welding technology of aluminium alloys by Friction Stir Welding (FSW). FSW is a very modern welding process with a great future use, primarily due to a variety of possible combinations of dissimilar materials to be welded. In this paper experimental results of butt welds for the friction stir welding of aluminium alloys are analyzed. A comparison hardness distribution in the welds was done considering welding parameters, that is the quantity of heat in the welding zone, panels thickness and aluminum alloy type.",
publisher = "DUZS - Društvo za unapređivanje zavarivanja u Srbiji, Beograd",
journal = "Zavarivanje i zavarene konstrukcije",
title = "Tehnologija zavarivanja aluminijumskih legura postupkom zavarivanja trenjem alatom, Welding technology of aluminium alloys using friction stir welding",
pages = "20-13",
number = "1",
volume = "55",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1647"
}

Veljić, D., Radović, N. A., Sedmak, A.,& Perović, M. M.. (2010). Tehnologija zavarivanja aluminijumskih legura postupkom zavarivanja trenjem alatom. in Zavarivanje i zavarene konstrukcije
DUZS - Društvo za unapređivanje zavarivanja u Srbiji, Beograd., 55(1), 13-20.
https://hdl.handle.net/21.15107/rcub_technorep_1647

Veljić D, Radović NA, Sedmak A, Perović MM. Tehnologija zavarivanja aluminijumskih legura postupkom zavarivanja trenjem alatom. in Zavarivanje i zavarene konstrukcije. 2010;55(1):13-20.
https://hdl.handle.net/21.15107/rcub_technorep_1647 .

Veljić, Darko, Radović, Nenad A., Sedmak, Aleksandar, Perović, Milenko M., "Tehnologija zavarivanja aluminijumskih legura postupkom zavarivanja trenjem alatom" in Zavarivanje i zavarene konstrukcije, 55, no. 1 (2010):13-20,
https://hdl.handle.net/21.15107/rcub_technorep_1647 .