TY  - JOUR
AU  - Đukić, Miloš
AU  - Bakić, Gordana
AU  - Zeravčić-Šijački, Vera
AU  - Sedmak, Aleksandar
AU  - Rajičić, Bratislav
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3050
AB  - Component failures due to the hydrogen embrittlement (HE) were observed in different industrial systems, including high-pressure hydrogen storage tanks, aircraft components, high-strength alloy components, and high-strength steel fasteners. The contemporary approach in studying the effects of hydrogen on the mechanical properties of steels and iron at different scales is based on the implementation of various multiscale (macro, micro-meso, and nano-atomic) modeling approaches and the applications of advanced experimental methods. A large number of contemporary studies confirmed the multiple effects and activity of different HE mechanisms in steels and iron. The coexistence and synergistic activity - concurrent action and effects in a cooperative manner of different HE mechanisms, including the hydrogen-enhanced localized plasticity (HELP) and the hydrogen-enhanced decohesion (HEDE), were recently detected and confirmed through computations-simulations, as well as experimentally in different grades of steel. However, the critical evaluation and quantification of synergy between the HELP and HEDE mechanisms, enhanced plasticity and decohesion, hydrogen-deformation/dislocation interactions and their simultaneous effect on the mechanical properties (hardening and softening), still do not exist. In this review paper, the multifaceted nature of the synergistic interplay of HE mechanisms is covered through extensive literature overview regarding the chronological development of ideas related to the HELP + HEDE concept and HELP mediated HEDE model. The particular emphasis is given to the proposal of the novel and unified HELP + HEDE model based on the specific microstructural mapping of the dominant HE mechanisms with implications on the fracture process and resulting hydrogen-assisted fracture modes. Most of up-to-date experimental and modeling approaches, current trends and future challenges in the investigation of the synergistic interplay of HE mechanisms in different grades of steel, including the most advanced, and iron, are also included and critically discussed.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Fracture Mechanics
T1  - The synergistic action and interplay of hydrogen embrittlement mechanisms in steels and iron: Localized plasticity and decohesion
VL  - 216
DO  - 10.1016/j.engfracmech.2019.106528
ER  - 

@article{
author = "Đukić, Miloš and Bakić, Gordana and Zeravčić-Šijački, Vera and Sedmak, Aleksandar and Rajičić, Bratislav",
year = "2019",
abstract = "Component failures due to the hydrogen embrittlement (HE) were observed in different industrial systems, including high-pressure hydrogen storage tanks, aircraft components, high-strength alloy components, and high-strength steel fasteners. The contemporary approach in studying the effects of hydrogen on the mechanical properties of steels and iron at different scales is based on the implementation of various multiscale (macro, micro-meso, and nano-atomic) modeling approaches and the applications of advanced experimental methods. A large number of contemporary studies confirmed the multiple effects and activity of different HE mechanisms in steels and iron. The coexistence and synergistic activity - concurrent action and effects in a cooperative manner of different HE mechanisms, including the hydrogen-enhanced localized plasticity (HELP) and the hydrogen-enhanced decohesion (HEDE), were recently detected and confirmed through computations-simulations, as well as experimentally in different grades of steel. However, the critical evaluation and quantification of synergy between the HELP and HEDE mechanisms, enhanced plasticity and decohesion, hydrogen-deformation/dislocation interactions and their simultaneous effect on the mechanical properties (hardening and softening), still do not exist. In this review paper, the multifaceted nature of the synergistic interplay of HE mechanisms is covered through extensive literature overview regarding the chronological development of ideas related to the HELP + HEDE concept and HELP mediated HEDE model. The particular emphasis is given to the proposal of the novel and unified HELP + HEDE model based on the specific microstructural mapping of the dominant HE mechanisms with implications on the fracture process and resulting hydrogen-assisted fracture modes. Most of up-to-date experimental and modeling approaches, current trends and future challenges in the investigation of the synergistic interplay of HE mechanisms in different grades of steel, including the most advanced, and iron, are also included and critically discussed.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Fracture Mechanics",
title = "The synergistic action and interplay of hydrogen embrittlement mechanisms in steels and iron: Localized plasticity and decohesion",
volume = "216",
doi = "10.1016/j.engfracmech.2019.106528"
}

Đukić, M., Bakić, G., Zeravčić-Šijački, V., Sedmak, A.,& Rajičić, B.. (2019). The synergistic action and interplay of hydrogen embrittlement mechanisms in steels and iron: Localized plasticity and decohesion. in Engineering Fracture Mechanics
Pergamon-Elsevier Science Ltd, Oxford., 216.
https://doi.org/10.1016/j.engfracmech.2019.106528

Đukić M, Bakić G, Zeravčić-Šijački V, Sedmak A, Rajičić B. The synergistic action and interplay of hydrogen embrittlement mechanisms in steels and iron: Localized plasticity and decohesion. in Engineering Fracture Mechanics. 2019;216.
doi:10.1016/j.engfracmech.2019.106528 .

Đukić, Miloš, Bakić, Gordana, Zeravčić-Šijački, Vera, Sedmak, Aleksandar, Rajičić, Bratislav, "The synergistic action and interplay of hydrogen embrittlement mechanisms in steels and iron: Localized plasticity and decohesion" in Engineering Fracture Mechanics, 216 (2019),
https://doi.org/10.1016/j.engfracmech.2019.106528 . .

TY  - CHAP
AU  - Bakić, Gordana
AU  - Đukić, Miloš
AU  - Rajičić, Bratislav
AU  - Zeravčić-Šijački, Vera
AU  - Maslarević, Aleksandar
AU  - Radović, Miladin
AU  - Maksimović, Vesna
AU  - Milošević, Nenad
PY  - 2017
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2538
AB  - The heat resistant tempered martensite ferritic steel X20CrMoV121 (DIN) has been extensively used within the last few decades as a material for boiler tubing systems and pipelines in thermal power plants (TPP). Long-term behavior of this steel is vastly researched and very well known, but main disadvantage is its poor weldability. In situ welding of martensitic steels is always challenging task and is usually quite difficult to implement properly in a short time, during forced outages of TPP. In this paper, characterization and mechanical properties of undermatch welded joint made during partial replacement of boiler outlet superheater (SH) in TPP by austenitic filler material, after 10 years of service are presented. Due to "cold" technique of welding, which does not required post weld heat treatment, this procedure were regular and widely used repair welding technique in two TPP (620 MW) units. In the purpose of comparison, two other type of matching welding joints of the same SH were also characterized: shop welded joint made by electrical resistance flash butt welding, as well as field welded joint made by gas tungsten arc welding during assembling of SH, which were both in service approximately 150,000 h.
PB  - Springer-Verlag Berlin, Berlin
T2  - Fracture At All Scales
T1  - Characterization of Tube Repair Weld in Thermal Power Plant Made of a 12% Cr Tempered Martensite Ferritic Steel
EP  - 169
SP  - 151
DO  - 10.1007/978-3-319-32634-4_8
ER  - 

@inbook{
author = "Bakić, Gordana and Đukić, Miloš and Rajičić, Bratislav and Zeravčić-Šijački, Vera and Maslarević, Aleksandar and Radović, Miladin and Maksimović, Vesna and Milošević, Nenad",
year = "2017",
abstract = "The heat resistant tempered martensite ferritic steel X20CrMoV121 (DIN) has been extensively used within the last few decades as a material for boiler tubing systems and pipelines in thermal power plants (TPP). Long-term behavior of this steel is vastly researched and very well known, but main disadvantage is its poor weldability. In situ welding of martensitic steels is always challenging task and is usually quite difficult to implement properly in a short time, during forced outages of TPP. In this paper, characterization and mechanical properties of undermatch welded joint made during partial replacement of boiler outlet superheater (SH) in TPP by austenitic filler material, after 10 years of service are presented. Due to "cold" technique of welding, which does not required post weld heat treatment, this procedure were regular and widely used repair welding technique in two TPP (620 MW) units. In the purpose of comparison, two other type of matching welding joints of the same SH were also characterized: shop welded joint made by electrical resistance flash butt welding, as well as field welded joint made by gas tungsten arc welding during assembling of SH, which were both in service approximately 150,000 h.",
publisher = "Springer-Verlag Berlin, Berlin",
journal = "Fracture At All Scales",
booktitle = "Characterization of Tube Repair Weld in Thermal Power Plant Made of a 12% Cr Tempered Martensite Ferritic Steel",
pages = "169-151",
doi = "10.1007/978-3-319-32634-4_8"
}

Bakić, G., Đukić, M., Rajičić, B., Zeravčić-Šijački, V., Maslarević, A., Radović, M., Maksimović, V.,& Milošević, N.. (2017). Characterization of Tube Repair Weld in Thermal Power Plant Made of a 12% Cr Tempered Martensite Ferritic Steel. in Fracture At All Scales
Springer-Verlag Berlin, Berlin., 151-169.
https://doi.org/10.1007/978-3-319-32634-4_8

Bakić G, Đukić M, Rajičić B, Zeravčić-Šijački V, Maslarević A, Radović M, Maksimović V, Milošević N. Characterization of Tube Repair Weld in Thermal Power Plant Made of a 12% Cr Tempered Martensite Ferritic Steel. in Fracture At All Scales. 2017;:151-169.
doi:10.1007/978-3-319-32634-4_8 .

Bakić, Gordana, Đukić, Miloš, Rajičić, Bratislav, Zeravčić-Šijački, Vera, Maslarević, Aleksandar, Radović, Miladin, Maksimović, Vesna, Milošević, Nenad, "Characterization of Tube Repair Weld in Thermal Power Plant Made of a 12% Cr Tempered Martensite Ferritic Steel" in Fracture At All Scales (2017):151-169,
https://doi.org/10.1007/978-3-319-32634-4_8 . .

TY  - CONF
AU  - Bakić, Gordana
AU  - Đukić, Miloš
AU  - Rajičić, Bratislav
AU  - Zeravčić-Šijački, Vera
AU  - Maslarević, Aleksandar
AU  - Milošević, Nenad
PY  - 2016
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2438
AB  - During service of thermal power plant (TPP) units, different components are exposed to high temperature due to technological cycle of TPP unit. Service lifetimes of these components, especially boiler heating surfaces, may be limited due to creep, fatigue or oxidation, but materials designed for use at high temperatures have been developed primarily for their creep properties and microstructural stability during long term exposures at elevated temperatures. Having in mind that oxidation in steam environment on the inner surface of boiler tubes and in flue gass on the outer surface of boler tubes could lead to a different consequences regarding service life of tubes, either directly through metal wastage or indirectly through raising local temperatures due to the lower thermal conductivity of the oxide scale, the oxidation behaviour of a different heat resistant steels become very important characteristics. In this paper are presented some data about the oxidation behavior of boiler tubes made of 2.25Cr1Mo and 12Cr1Mo0.3V steel after service of approximately 130.000 and 200.000h in two 620MVV TPP units. Characterization of oxide scales on the inner side on tubes made of two steels with different chromium content, after two different prolonged periods of service, were compared and also their influence on the service life of tubes and kinetics of oxide scale growth were analyzed.
PB  - Elsevier Science Bv, Amsterdam
C3  - Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21)
T1  - Oxidation behavior during prolonged service of boiler tubes made of 2.25Cr1Mo and 12Cr1Mo0.3V heat resistance steels
EP  - 3653
SP  - 3647
VL  - 2
DO  - 10.1016/j.prostr.2016.06.453
ER  - 

@conference{
author = "Bakić, Gordana and Đukić, Miloš and Rajičić, Bratislav and Zeravčić-Šijački, Vera and Maslarević, Aleksandar and Milošević, Nenad",
year = "2016",
abstract = "During service of thermal power plant (TPP) units, different components are exposed to high temperature due to technological cycle of TPP unit. Service lifetimes of these components, especially boiler heating surfaces, may be limited due to creep, fatigue or oxidation, but materials designed for use at high temperatures have been developed primarily for their creep properties and microstructural stability during long term exposures at elevated temperatures. Having in mind that oxidation in steam environment on the inner surface of boiler tubes and in flue gass on the outer surface of boler tubes could lead to a different consequences regarding service life of tubes, either directly through metal wastage or indirectly through raising local temperatures due to the lower thermal conductivity of the oxide scale, the oxidation behaviour of a different heat resistant steels become very important characteristics. In this paper are presented some data about the oxidation behavior of boiler tubes made of 2.25Cr1Mo and 12Cr1Mo0.3V steel after service of approximately 130.000 and 200.000h in two 620MVV TPP units. Characterization of oxide scales on the inner side on tubes made of two steels with different chromium content, after two different prolonged periods of service, were compared and also their influence on the service life of tubes and kinetics of oxide scale growth were analyzed.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21)",
title = "Oxidation behavior during prolonged service of boiler tubes made of 2.25Cr1Mo and 12Cr1Mo0.3V heat resistance steels",
pages = "3653-3647",
volume = "2",
doi = "10.1016/j.prostr.2016.06.453"
}

Bakić, G., Đukić, M., Rajičić, B., Zeravčić-Šijački, V., Maslarević, A.,& Milošević, N.. (2016). Oxidation behavior during prolonged service of boiler tubes made of 2.25Cr1Mo and 12Cr1Mo0.3V heat resistance steels. in Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21)
Elsevier Science Bv, Amsterdam., 2, 3647-3653.
https://doi.org/10.1016/j.prostr.2016.06.453

Bakić G, Đukić M, Rajičić B, Zeravčić-Šijački V, Maslarević A, Milošević N. Oxidation behavior during prolonged service of boiler tubes made of 2.25Cr1Mo and 12Cr1Mo0.3V heat resistance steels. in Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21). 2016;2:3647-3653.
doi:10.1016/j.prostr.2016.06.453 .

Bakić, Gordana, Đukić, Miloš, Rajičić, Bratislav, Zeravčić-Šijački, Vera, Maslarević, Aleksandar, Milošević, Nenad, "Oxidation behavior during prolonged service of boiler tubes made of 2.25Cr1Mo and 12Cr1Mo0.3V heat resistance steels" in Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21), 2 (2016):3647-3653,
https://doi.org/10.1016/j.prostr.2016.06.453 . .

TY  - CONF
AU  - Đukić, Miloš
AU  - Bakić, Gordana
AU  - Zeravčić-Šijački, Vera
AU  - Rajičić, Bratislav
AU  - Sedmak, Aleksandar
AU  - Mitrović, Radivoje
AU  - Mišković, Žarko
PY  - 2016
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2466
AB  - Bearing in mind the multiple effects of hydrogen in steels, the specific mechanism of hydrogen embrittlement (HE) is active, depending on the experimental conditions and numerous factors which can be grouped as environmental, mechanical and material influences. A large number of contemporary studies and models about hydrogen environment assisted cracking and HE in steels are presented in the form of critical review in this paper. This critical review represent the necessary background for the development of a multiscale structural integrity model based on correlation between simultaneously active HE micromechanisms: the hydrogen-enhanced localized plasticity (HELP) and the hydrogen-enhanced decohesion (HEDE) (HELP+HEDE) and macro-mechanical response of material, unevenly enriched with hydrogen during service of boiler tubes in thermal fossil fuel power plant. Several different experimental methods and techniques were used to determine the boiler tube failure mechanism and afterwards also the viable HE mechanisms in the investigated ferritic-pearlitic low carbon steel, grade 20 - St.20 (equivalent to AISI 1020). That represent a background for the development of a structural integrity model based on the correlation of material macro-mechanical properties to scanning electron microscopy fractography analysis of fracture surfaces of Charpy specimens, in the presence of confirmed and simultaneously active HE micro-mechanisms (HELP+HEDE) in steel. The aim of this paper is to show how to implement what we have learned from theoretical HE models into the field to provide industry with valuable data and practical structural integrity model.
PB  - Elsevier Science Bv, Amsterdam
C3  - Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21)
T1  - Towards a unified and practical industrial model for prediction of hydrogen embrittlement and damage in steels
EP  - 611
SP  - 604
VL  - 2
DO  - 10.1016/j.prostr.2016.06.078
ER  - 

@conference{
author = "Đukić, Miloš and Bakić, Gordana and Zeravčić-Šijački, Vera and Rajičić, Bratislav and Sedmak, Aleksandar and Mitrović, Radivoje and Mišković, Žarko",
year = "2016",
abstract = "Bearing in mind the multiple effects of hydrogen in steels, the specific mechanism of hydrogen embrittlement (HE) is active, depending on the experimental conditions and numerous factors which can be grouped as environmental, mechanical and material influences. A large number of contemporary studies and models about hydrogen environment assisted cracking and HE in steels are presented in the form of critical review in this paper. This critical review represent the necessary background for the development of a multiscale structural integrity model based on correlation between simultaneously active HE micromechanisms: the hydrogen-enhanced localized plasticity (HELP) and the hydrogen-enhanced decohesion (HEDE) (HELP+HEDE) and macro-mechanical response of material, unevenly enriched with hydrogen during service of boiler tubes in thermal fossil fuel power plant. Several different experimental methods and techniques were used to determine the boiler tube failure mechanism and afterwards also the viable HE mechanisms in the investigated ferritic-pearlitic low carbon steel, grade 20 - St.20 (equivalent to AISI 1020). That represent a background for the development of a structural integrity model based on the correlation of material macro-mechanical properties to scanning electron microscopy fractography analysis of fracture surfaces of Charpy specimens, in the presence of confirmed and simultaneously active HE micro-mechanisms (HELP+HEDE) in steel. The aim of this paper is to show how to implement what we have learned from theoretical HE models into the field to provide industry with valuable data and practical structural integrity model.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21)",
title = "Towards a unified and practical industrial model for prediction of hydrogen embrittlement and damage in steels",
pages = "611-604",
volume = "2",
doi = "10.1016/j.prostr.2016.06.078"
}

Đukić, M., Bakić, G., Zeravčić-Šijački, V., Rajičić, B., Sedmak, A., Mitrović, R.,& Mišković, Ž.. (2016). Towards a unified and practical industrial model for prediction of hydrogen embrittlement and damage in steels. in Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21)
Elsevier Science Bv, Amsterdam., 2, 604-611.
https://doi.org/10.1016/j.prostr.2016.06.078

Đukić M, Bakić G, Zeravčić-Šijački V, Rajičić B, Sedmak A, Mitrović R, Mišković Ž. Towards a unified and practical industrial model for prediction of hydrogen embrittlement and damage in steels. in Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21). 2016;2:604-611.
doi:10.1016/j.prostr.2016.06.078 .

Đukić, Miloš, Bakić, Gordana, Zeravčić-Šijački, Vera, Rajičić, Bratislav, Sedmak, Aleksandar, Mitrović, Radivoje, Mišković, Žarko, "Towards a unified and practical industrial model for prediction of hydrogen embrittlement and damage in steels" in Procedia Structural Integrity - 21st European Conference on Fracture, (Ecf21), 2 (2016):604-611,
https://doi.org/10.1016/j.prostr.2016.06.078 . .

TY  - JOUR
AU  - Đukić, Miloš
AU  - Bakić, Gordana
AU  - Zeravčić-Šijački, Vera
AU  - Sedmak, Aleksandar
AU  - Rajičić, Bratislav
PY  - 2016
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2485
AB  - Hydrogen embrittlement is a common, dangerous, and poorly understood cause of failure in many metal alloys. In practice, it is observed that different types of damage to industrial components have been tied to the presence and localization of hydrogen in metals. Many efforts have been made at understanding the effects of hydrogen on materials, resulting in an abundance of theoretical models and papers. However, a fully developed and practically-applicable predictive physical model still does not exist industrially for predicting and preventing hydrogen embrittlement. The connection of microstructure-based behaviors of materials and effects on the macroscopic measurable characteristics (stress levels, hardness, strength, and impact toughness) is of the utmost importance to achieve a unified model for hydrogen embrittlement. This paper gives an overview of the application of a model for structural integrity analysis of boiler tubes made of plain carbon steel exposed during operation to a local corrosion process and multiple hydrogen assisted degradation processes: hydrogen embrittlement and high-temperature hydrogen attack. The model is based on the correlation of mechanical properties to scanning electron microscopy fractography analysis of fracture surfaces in the presence of simultaneously active hydrogen embrittlement micromechanisms. The proposed model is practical for use as a predictive maintenance in power plants, as it is based on the use of standard macro-mechanical tests.
PB  - Natl Assoc Corrosion Eng, Houston
T2  - Corrosion
T1  - Hydrogen Embrittlement of Industrial Components: Prediction, Prevention, and Models
EP  - 961
IS  - 7
SP  - 943
VL  - 72
DO  - 10.5006/1958
ER  - 

@article{
author = "Đukić, Miloš and Bakić, Gordana and Zeravčić-Šijački, Vera and Sedmak, Aleksandar and Rajičić, Bratislav",
year = "2016",
abstract = "Hydrogen embrittlement is a common, dangerous, and poorly understood cause of failure in many metal alloys. In practice, it is observed that different types of damage to industrial components have been tied to the presence and localization of hydrogen in metals. Many efforts have been made at understanding the effects of hydrogen on materials, resulting in an abundance of theoretical models and papers. However, a fully developed and practically-applicable predictive physical model still does not exist industrially for predicting and preventing hydrogen embrittlement. The connection of microstructure-based behaviors of materials and effects on the macroscopic measurable characteristics (stress levels, hardness, strength, and impact toughness) is of the utmost importance to achieve a unified model for hydrogen embrittlement. This paper gives an overview of the application of a model for structural integrity analysis of boiler tubes made of plain carbon steel exposed during operation to a local corrosion process and multiple hydrogen assisted degradation processes: hydrogen embrittlement and high-temperature hydrogen attack. The model is based on the correlation of mechanical properties to scanning electron microscopy fractography analysis of fracture surfaces in the presence of simultaneously active hydrogen embrittlement micromechanisms. The proposed model is practical for use as a predictive maintenance in power plants, as it is based on the use of standard macro-mechanical tests.",
publisher = "Natl Assoc Corrosion Eng, Houston",
journal = "Corrosion",
title = "Hydrogen Embrittlement of Industrial Components: Prediction, Prevention, and Models",
pages = "961-943",
number = "7",
volume = "72",
doi = "10.5006/1958"
}

Đukić, M., Bakić, G., Zeravčić-Šijački, V., Sedmak, A.,& Rajičić, B.. (2016). Hydrogen Embrittlement of Industrial Components: Prediction, Prevention, and Models. in Corrosion
Natl Assoc Corrosion Eng, Houston., 72(7), 943-961.
https://doi.org/10.5006/1958

Đukić M, Bakić G, Zeravčić-Šijački V, Sedmak A, Rajičić B. Hydrogen Embrittlement of Industrial Components: Prediction, Prevention, and Models. in Corrosion. 2016;72(7):943-961.
doi:10.5006/1958 .

Đukić, Miloš, Bakić, Gordana, Zeravčić-Šijački, Vera, Sedmak, Aleksandar, Rajičić, Bratislav, "Hydrogen Embrittlement of Industrial Components: Prediction, Prevention, and Models" in Corrosion, 72, no. 7 (2016):943-961,
https://doi.org/10.5006/1958 . .

TY  - JOUR
AU  - Đukić, Miloš
AU  - Zeravčić-Šijački, Vera
AU  - Bakić, Gordana
AU  - Sedmak, Aleksandar
AU  - Rajičić, Bratislav
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2229
AB  - Many efforts have been made to understand the effects of hydrogen on steels, resulting in an abundance of theoretical models and papers. However, a fully developed and practically applicable predictive physical model still does not exist industrially for predicting and preventing hydrogen damage. In practice, it is observed that different types of damages to industrial boiler components have been associated with the presence and localization of hydrogen in metals. In this paper, a damaged boiler tube made of grade 20 - St. 20 (or 20G, equivalent to AISI 1020) was investigated. The experimental research was conducted in two distinctive phases: failure analysis of the boiler evaporator tube sample and subsequent postmortem analysis of the viable hydrogen embrittlement mechanisms (HE) in St. 20 steel. Numerous tested samples were cut out from the boiler tubes of fossil fuel power plant, damaged due to high temperature hydrogen attack (HTHA) during service, as a result of the development of hydrogen-induced corrosion process. Samples were prepared for the chemical composition analysis, tube wall thickness measurement, tensile testing, hardness measurement, impact strength testing (on instrumented Charpy machine), analysis of the chemical composition of corrosion products - deposit and the microstructural characterization by optical and scanning electron microscopy SEM/EDX. The HTHA damage mechanism is a primary cause of boiler tube fracture. Based on the multi-scale special model, applied in subsequent postmortem investigations, the results indicate a simultaneous action of the hydrogen-enhanced decohesion (HEDE) and hydrogen-enhanced localized plasticity (HELP) mechanisms of HE, depending on the local concentration of hydrogen in investigated steel. The model is based on the correlation of mechanical properties to the SEM fractography analysis of fracture surfaces.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Hydrogen damage of steels: A case study and hydrogen embrittlement model
EP  - 498
SP  - 485
VL  - 58
DO  - 10.1016/j.engfailanal.2015.05.017
ER  - 

@article{
author = "Đukić, Miloš and Zeravčić-Šijački, Vera and Bakić, Gordana and Sedmak, Aleksandar and Rajičić, Bratislav",
year = "2015",
abstract = "Many efforts have been made to understand the effects of hydrogen on steels, resulting in an abundance of theoretical models and papers. However, a fully developed and practically applicable predictive physical model still does not exist industrially for predicting and preventing hydrogen damage. In practice, it is observed that different types of damages to industrial boiler components have been associated with the presence and localization of hydrogen in metals. In this paper, a damaged boiler tube made of grade 20 - St. 20 (or 20G, equivalent to AISI 1020) was investigated. The experimental research was conducted in two distinctive phases: failure analysis of the boiler evaporator tube sample and subsequent postmortem analysis of the viable hydrogen embrittlement mechanisms (HE) in St. 20 steel. Numerous tested samples were cut out from the boiler tubes of fossil fuel power plant, damaged due to high temperature hydrogen attack (HTHA) during service, as a result of the development of hydrogen-induced corrosion process. Samples were prepared for the chemical composition analysis, tube wall thickness measurement, tensile testing, hardness measurement, impact strength testing (on instrumented Charpy machine), analysis of the chemical composition of corrosion products - deposit and the microstructural characterization by optical and scanning electron microscopy SEM/EDX. The HTHA damage mechanism is a primary cause of boiler tube fracture. Based on the multi-scale special model, applied in subsequent postmortem investigations, the results indicate a simultaneous action of the hydrogen-enhanced decohesion (HEDE) and hydrogen-enhanced localized plasticity (HELP) mechanisms of HE, depending on the local concentration of hydrogen in investigated steel. The model is based on the correlation of mechanical properties to the SEM fractography analysis of fracture surfaces.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Hydrogen damage of steels: A case study and hydrogen embrittlement model",
pages = "498-485",
volume = "58",
doi = "10.1016/j.engfailanal.2015.05.017"
}

Đukić, M., Zeravčić-Šijački, V., Bakić, G., Sedmak, A.,& Rajičić, B.. (2015). Hydrogen damage of steels: A case study and hydrogen embrittlement model. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 58, 485-498.
https://doi.org/10.1016/j.engfailanal.2015.05.017

Đukić M, Zeravčić-Šijački V, Bakić G, Sedmak A, Rajičić B. Hydrogen damage of steels: A case study and hydrogen embrittlement model. in Engineering Failure Analysis. 2015;58:485-498.
doi:10.1016/j.engfailanal.2015.05.017 .

Đukić, Miloš, Zeravčić-Šijački, Vera, Bakić, Gordana, Sedmak, Aleksandar, Rajičić, Bratislav, "Hydrogen damage of steels: A case study and hydrogen embrittlement model" in Engineering Failure Analysis, 58 (2015):485-498,
https://doi.org/10.1016/j.engfailanal.2015.05.017 . .

TY  - CONF
AU  - Đukić, Miloš
AU  - Zeravčić-Šijački, Vera
AU  - Bakić, Gordana
AU  - Sedmak, Aleksandar
AU  - Rajičić, Bratislav
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2023
AB  - Hydrogen embrittlement (HE) of steels is extremely interesting topic in many industrial applications, while a predictive physical model still does not exist. A number of studies carried out in the world are unambiguous confirmation of that statement. Bearing in mind multiple effects of hydrogen in certain metals, the specific mechanism of hydrogen embrittlement is manifested, depending on the experimental conditions. In this paper structural, low carbon steel, for pressure purposes, grade 20- St.20 (GOST 1050-88) was investigated. Numerous tested samples were cut out from the boiler tubes of fossil fuel power plant, damaged due to high temperature hydrogen attack and HE during service, as a result of the development of hydrogen-induced corrosion process. Samples were prepared for the chemical composition analysis, hardness measurement, impact strength testing (on instrumented Charpy machine) and microstructural characterization by optical and scanning electron microscopy - SEM/EDX. Based on multi-scale special approach, applied in experimental investigations, the results, presented in this paper, indicate the simultaneous action of the hydrogen-enhanced decohesion (HEDE) and hydrogen enhanced localized plasticity (HELP) mechanisms of HE, depending on the local concentration of hydrogen in investigated steel. These results are consistent with some models proposed in literature, about a possible simultaneous action of the HELP and HEDE mechanisms in metallic materials.
PB  - Elsevier Science Bv, Amsterdam
C3  - 20th European Conference on Fracture
T1  - Hydrogen embrittlement of low carbon structural steel
EP  - 1172
SP  - 1167
VL  - 3
DO  - 10.1016/j.mspro.2014.06.190
ER  - 

@conference{
author = "Đukić, Miloš and Zeravčić-Šijački, Vera and Bakić, Gordana and Sedmak, Aleksandar and Rajičić, Bratislav",
year = "2014",
abstract = "Hydrogen embrittlement (HE) of steels is extremely interesting topic in many industrial applications, while a predictive physical model still does not exist. A number of studies carried out in the world are unambiguous confirmation of that statement. Bearing in mind multiple effects of hydrogen in certain metals, the specific mechanism of hydrogen embrittlement is manifested, depending on the experimental conditions. In this paper structural, low carbon steel, for pressure purposes, grade 20- St.20 (GOST 1050-88) was investigated. Numerous tested samples were cut out from the boiler tubes of fossil fuel power plant, damaged due to high temperature hydrogen attack and HE during service, as a result of the development of hydrogen-induced corrosion process. Samples were prepared for the chemical composition analysis, hardness measurement, impact strength testing (on instrumented Charpy machine) and microstructural characterization by optical and scanning electron microscopy - SEM/EDX. Based on multi-scale special approach, applied in experimental investigations, the results, presented in this paper, indicate the simultaneous action of the hydrogen-enhanced decohesion (HEDE) and hydrogen enhanced localized plasticity (HELP) mechanisms of HE, depending on the local concentration of hydrogen in investigated steel. These results are consistent with some models proposed in literature, about a possible simultaneous action of the HELP and HEDE mechanisms in metallic materials.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "20th European Conference on Fracture",
title = "Hydrogen embrittlement of low carbon structural steel",
pages = "1172-1167",
volume = "3",
doi = "10.1016/j.mspro.2014.06.190"
}

Đukić, M., Zeravčić-Šijački, V., Bakić, G., Sedmak, A.,& Rajičić, B.. (2014). Hydrogen embrittlement of low carbon structural steel. in 20th European Conference on Fracture
Elsevier Science Bv, Amsterdam., 3, 1167-1172.
https://doi.org/10.1016/j.mspro.2014.06.190

Đukić M, Zeravčić-Šijački V, Bakić G, Sedmak A, Rajičić B. Hydrogen embrittlement of low carbon structural steel. in 20th European Conference on Fracture. 2014;3:1167-1172.
doi:10.1016/j.mspro.2014.06.190 .

Đukić, Miloš, Zeravčić-Šijački, Vera, Bakić, Gordana, Sedmak, Aleksandar, Rajičić, Bratislav, "Hydrogen embrittlement of low carbon structural steel" in 20th European Conference on Fracture, 3 (2014):1167-1172,
https://doi.org/10.1016/j.mspro.2014.06.190 . .

TY  - CONF
AU  - Bakić, Gordana
AU  - Zeravčić-Šijački, Vera
AU  - Đukić, Miloš
AU  - Perunicić, V.
AU  - Prodanović, A.
AU  - Rajičić, Bratislav
AU  - Gajić, I.
AU  - Sekeljić, P.
AU  - Gregorjev, N.
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2017
AB  - Martensitic steel X20CrMo12.1 has been extensively used within the last few decades as a material for tubing systems and pipelines in thermal power plants (TPP). Long term behavior of this steel is very well known and understood and because of that was found to be reliable material for prolonged service at elevated temperatures. It is well known that during operation TPP components are subject to microstructural changes that inevitably reflect decrease in their mechanical properties that lead to the loss of structural integrity and serviceability of component. This paper deals with the comprehensive investigation carried out on the main steam gate valve parent material of welded joint, as a part of main steam pipeline, after 170.000 h of service (545 degrees C and 19MPa). The obtained results showed that the microstructural degradation caused by long term operation had little effects on the hardness and strength of material, while the changes in impact toughness were observed. Comprehensive microstructural analysis included the examination of the microstructure on the surface and trough the wall thickness.
PB  - Elsevier Science Bv, Amsterdam
C3  - 20th European Conference on Fracture
T1  - Material characterization of the main steam gate valve made of X20CrMoV 12.1 steel after long term service
EP  - 1517
SP  - 1512
VL  - 3
DO  - 10.1016/j.mspro.2014.06.244
ER  - 

@conference{
author = "Bakić, Gordana and Zeravčić-Šijački, Vera and Đukić, Miloš and Perunicić, V. and Prodanović, A. and Rajičić, Bratislav and Gajić, I. and Sekeljić, P. and Gregorjev, N.",
year = "2014",
abstract = "Martensitic steel X20CrMo12.1 has been extensively used within the last few decades as a material for tubing systems and pipelines in thermal power plants (TPP). Long term behavior of this steel is very well known and understood and because of that was found to be reliable material for prolonged service at elevated temperatures. It is well known that during operation TPP components are subject to microstructural changes that inevitably reflect decrease in their mechanical properties that lead to the loss of structural integrity and serviceability of component. This paper deals with the comprehensive investigation carried out on the main steam gate valve parent material of welded joint, as a part of main steam pipeline, after 170.000 h of service (545 degrees C and 19MPa). The obtained results showed that the microstructural degradation caused by long term operation had little effects on the hardness and strength of material, while the changes in impact toughness were observed. Comprehensive microstructural analysis included the examination of the microstructure on the surface and trough the wall thickness.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "20th European Conference on Fracture",
title = "Material characterization of the main steam gate valve made of X20CrMoV 12.1 steel after long term service",
pages = "1517-1512",
volume = "3",
doi = "10.1016/j.mspro.2014.06.244"
}

Bakić, G., Zeravčić-Šijački, V., Đukić, M., Perunicić, V., Prodanović, A., Rajičić, B., Gajić, I., Sekeljić, P.,& Gregorjev, N.. (2014). Material characterization of the main steam gate valve made of X20CrMoV 12.1 steel after long term service. in 20th European Conference on Fracture
Elsevier Science Bv, Amsterdam., 3, 1512-1517.
https://doi.org/10.1016/j.mspro.2014.06.244

Bakić G, Zeravčić-Šijački V, Đukić M, Perunicić V, Prodanović A, Rajičić B, Gajić I, Sekeljić P, Gregorjev N. Material characterization of the main steam gate valve made of X20CrMoV 12.1 steel after long term service. in 20th European Conference on Fracture. 2014;3:1512-1517.
doi:10.1016/j.mspro.2014.06.244 .

Bakić, Gordana, Zeravčić-Šijački, Vera, Đukić, Miloš, Perunicić, V., Prodanović, A., Rajičić, Bratislav, Gajić, I., Sekeljić, P., Gregorjev, N., "Material characterization of the main steam gate valve made of X20CrMoV 12.1 steel after long term service" in 20th European Conference on Fracture, 3 (2014):1512-1517,
https://doi.org/10.1016/j.mspro.2014.06.244 . .

TY  - JOUR
AU  - Žunjić, Aleksandar
AU  - Sremcević, Vladimir
AU  - Zeravčić-Šijački, Vera
AU  - Sijacki, Ana
PY  - 2012
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1453
AB  - In this study, a research of injuries of passengers in city buses is presented, which are not a consequence of collision of buses with other objects. The number of injured passengers in the territory of Belgrade was registered, during three consecutive years. Most frequently injured body part was the head, while women over the age of 60 are the most vulnerable population of passengers. The most often reason for the appearance of injuries was the effect of acceleration. Also, it is pointed out to the importance of consideration of the problem of multiple injuries. These injuries are more complex than the individual ones, and they may indicate to the existence of greater omissions in the design of the interior of the bus. Proposals for certain system solutions, as well as some recommendations for designing are given, which can improve the safety of passengers who use the city bus as a means of transportation.
PB  - IOS Press, Amsterdam
T2  - Work-A Journal of Prevention Assessment & Rehabilitation
T1  - Research of injuries of passengers in city buses as a consequence of non-collision effects
EP  - 4950
SP  - 4943
VL  - 41
DO  - 10.3233/WOR-2012-0790-4943
ER  - 

@article{
author = "Žunjić, Aleksandar and Sremcević, Vladimir and Zeravčić-Šijački, Vera and Sijacki, Ana",
year = "2012",
abstract = "In this study, a research of injuries of passengers in city buses is presented, which are not a consequence of collision of buses with other objects. The number of injured passengers in the territory of Belgrade was registered, during three consecutive years. Most frequently injured body part was the head, while women over the age of 60 are the most vulnerable population of passengers. The most often reason for the appearance of injuries was the effect of acceleration. Also, it is pointed out to the importance of consideration of the problem of multiple injuries. These injuries are more complex than the individual ones, and they may indicate to the existence of greater omissions in the design of the interior of the bus. Proposals for certain system solutions, as well as some recommendations for designing are given, which can improve the safety of passengers who use the city bus as a means of transportation.",
publisher = "IOS Press, Amsterdam",
journal = "Work-A Journal of Prevention Assessment & Rehabilitation",
title = "Research of injuries of passengers in city buses as a consequence of non-collision effects",
pages = "4950-4943",
volume = "41",
doi = "10.3233/WOR-2012-0790-4943"
}

Žunjić, A., Sremcević, V., Zeravčić-Šijački, V.,& Sijacki, A.. (2012). Research of injuries of passengers in city buses as a consequence of non-collision effects. in Work-A Journal of Prevention Assessment & Rehabilitation
IOS Press, Amsterdam., 41, 4943-4950.
https://doi.org/10.3233/WOR-2012-0790-4943

Žunjić A, Sremcević V, Zeravčić-Šijački V, Sijacki A. Research of injuries of passengers in city buses as a consequence of non-collision effects. in Work-A Journal of Prevention Assessment & Rehabilitation. 2012;41:4943-4950.
doi:10.3233/WOR-2012-0790-4943 .

Žunjić, Aleksandar, Sremcević, Vladimir, Zeravčić-Šijački, Vera, Sijacki, Ana, "Research of injuries of passengers in city buses as a consequence of non-collision effects" in Work-A Journal of Prevention Assessment & Rehabilitation, 41 (2012):4943-4950,
https://doi.org/10.3233/WOR-2012-0790-4943 . .

TY  - JOUR
AU  - Zeravčić-Šijački, Vera
AU  - Bakić, Gordana
AU  - Đukić, Miloš
AU  - Marković, Dragomir
AU  - Rajičić, Bratislav
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1004
AB  - Reliability centered maintenance (RCM) has a key role in the quality system of thermal power plants. Electricity production is definitely not only production of a product, but also becomes a customer service. Reliability is the top quality tier of this service. Incorporation in the Integrated energy system means fast transformations of organization on all levels. The reliability of modern generation components basically influences the efficiency and capacity of a power plant as a whole. This paper presents the results of RCM practice of one 620 MW thermal power plant. RCM implementation on current problems during exploitation emphasized problems with the boiler tubing system. The methodological approach included outages analyses, marking of the most significant ones, determination of main causes of damage (determination of the material exhaustion state based on expert analyses), application of adequate remaining life assessment methodology and finally the recommendations. Based on these analyses, certain technical solutions were performed and as a result, the mean time between failures of the plant increased, as well as its reliability. According to cost efficiency, RCM methodology presented the most effective cost-benefit method for reliability upgrade.
T2  - Technics Technologies Education Management
T1  - Contemporary Maintenance Management of Power Plant Life Exhaustion Components
EP  - 436
IS  - 3
SP  - 431
VL  - 5
UR  - https://hdl.handle.net/21.15107/rcub_machinery_1004
ER  - 

@article{
author = "Zeravčić-Šijački, Vera and Bakić, Gordana and Đukić, Miloš and Marković, Dragomir and Rajičić, Bratislav",
year = "2010",
abstract = "Reliability centered maintenance (RCM) has a key role in the quality system of thermal power plants. Electricity production is definitely not only production of a product, but also becomes a customer service. Reliability is the top quality tier of this service. Incorporation in the Integrated energy system means fast transformations of organization on all levels. The reliability of modern generation components basically influences the efficiency and capacity of a power plant as a whole. This paper presents the results of RCM practice of one 620 MW thermal power plant. RCM implementation on current problems during exploitation emphasized problems with the boiler tubing system. The methodological approach included outages analyses, marking of the most significant ones, determination of main causes of damage (determination of the material exhaustion state based on expert analyses), application of adequate remaining life assessment methodology and finally the recommendations. Based on these analyses, certain technical solutions were performed and as a result, the mean time between failures of the plant increased, as well as its reliability. According to cost efficiency, RCM methodology presented the most effective cost-benefit method for reliability upgrade.",
journal = "Technics Technologies Education Management",
title = "Contemporary Maintenance Management of Power Plant Life Exhaustion Components",
pages = "436-431",
number = "3",
volume = "5",
url = "https://hdl.handle.net/21.15107/rcub_machinery_1004"
}

Zeravčić-Šijački, V., Bakić, G., Đukić, M., Marković, D.,& Rajičić, B.. (2010). Contemporary Maintenance Management of Power Plant Life Exhaustion Components. in Technics Technologies Education Management, 5(3), 431-436.
https://hdl.handle.net/21.15107/rcub_machinery_1004

Zeravčić-Šijački V, Bakić G, Đukić M, Marković D, Rajičić B. Contemporary Maintenance Management of Power Plant Life Exhaustion Components. in Technics Technologies Education Management. 2010;5(3):431-436.
https://hdl.handle.net/21.15107/rcub_machinery_1004 .

Zeravčić-Šijački, Vera, Bakić, Gordana, Đukić, Miloš, Marković, Dragomir, Rajičić, Bratislav, "Contemporary Maintenance Management of Power Plant Life Exhaustion Components" in Technics Technologies Education Management, 5, no. 3 (2010):431-436,
https://hdl.handle.net/21.15107/rcub_machinery_1004 .

TY  - JOUR
AU  - Sijacki, Ana
AU  - Zeravčić-Šijački, Vera
AU  - Bakić, Gordana
AU  - Cosović, Vlada
AU  - Ristić, Zoran
AU  - Karamarković, Aleksandar
AU  - Popović, Nada
AU  - Djukić, Vladimir
AU  - Bajec, Đorđe
AU  - Blagojević, Zoran
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/886
AB  - Background/Aims: Today, treatment of human calculi, and particularly those of gallbladder, is, to a large extent, less invasive procedure due to numerous non-invasive methods that have been developed. Methodology: CO 2 laser of pulse (output 5W)(W-watt, SI unit system) and continual mode (output 15W) and diode laser (808nm-nanometer, SI) were used for tests of fragmentation of gallbladder calculi in vitro. Results: A total of 15 human gallbladder calculi of known size were examined, which had been collected during surgical interventions. Damages caused by laser were examined visually and by stereo-microscope (10 to 25 times magnification). During testing, the dependence of fragmentation on the type of laser effect, as well as the degree of fragmentation on the type of tested calculus was noted. Different types and dimensions of damage caused by various laser beams, as well as coloration changes of superficial layers in relation to the type of tested calculi was noticed. Conclusion: Accordingly, in this specific case, the priority for removal of gallbladder calculi by ablation will be given to diode laser.
T2  - Hepato-Gastroenterology
T1  - Laser-Induced Damages of Different Types of Human Gallbladder Stones
EP  - 949
IS  - 93
SP  - 946
VL  - 56
UR  - https://hdl.handle.net/21.15107/rcub_machinery_886
ER  - 

@article{
author = "Sijacki, Ana and Zeravčić-Šijački, Vera and Bakić, Gordana and Cosović, Vlada and Ristić, Zoran and Karamarković, Aleksandar and Popović, Nada and Djukić, Vladimir and Bajec, Đorđe and Blagojević, Zoran",
year = "2009",
abstract = "Background/Aims: Today, treatment of human calculi, and particularly those of gallbladder, is, to a large extent, less invasive procedure due to numerous non-invasive methods that have been developed. Methodology: CO 2 laser of pulse (output 5W)(W-watt, SI unit system) and continual mode (output 15W) and diode laser (808nm-nanometer, SI) were used for tests of fragmentation of gallbladder calculi in vitro. Results: A total of 15 human gallbladder calculi of known size were examined, which had been collected during surgical interventions. Damages caused by laser were examined visually and by stereo-microscope (10 to 25 times magnification). During testing, the dependence of fragmentation on the type of laser effect, as well as the degree of fragmentation on the type of tested calculus was noted. Different types and dimensions of damage caused by various laser beams, as well as coloration changes of superficial layers in relation to the type of tested calculi was noticed. Conclusion: Accordingly, in this specific case, the priority for removal of gallbladder calculi by ablation will be given to diode laser.",
journal = "Hepato-Gastroenterology",
title = "Laser-Induced Damages of Different Types of Human Gallbladder Stones",
pages = "949-946",
number = "93",
volume = "56",
url = "https://hdl.handle.net/21.15107/rcub_machinery_886"
}

Sijacki, A., Zeravčić-Šijački, V., Bakić, G., Cosović, V., Ristić, Z., Karamarković, A., Popović, N., Djukić, V., Bajec, Đ.,& Blagojević, Z.. (2009). Laser-Induced Damages of Different Types of Human Gallbladder Stones. in Hepato-Gastroenterology, 56(93), 946-949.
https://hdl.handle.net/21.15107/rcub_machinery_886

Sijacki A, Zeravčić-Šijački V, Bakić G, Cosović V, Ristić Z, Karamarković A, Popović N, Djukić V, Bajec Đ, Blagojević Z. Laser-Induced Damages of Different Types of Human Gallbladder Stones. in Hepato-Gastroenterology. 2009;56(93):946-949.
https://hdl.handle.net/21.15107/rcub_machinery_886 .

Sijacki, Ana, Zeravčić-Šijački, Vera, Bakić, Gordana, Cosović, Vlada, Ristić, Zoran, Karamarković, Aleksandar, Popović, Nada, Djukić, Vladimir, Bajec, Đorđe, Blagojević, Zoran, "Laser-Induced Damages of Different Types of Human Gallbladder Stones" in Hepato-Gastroenterology, 56, no. 93 (2009):946-949,
https://hdl.handle.net/21.15107/rcub_machinery_886 .

TY  - CONF
AU  - Zeravčić-Šijački, Vera
AU  - Bakić, Gordana
AU  - Đukić, Miloš
AU  - Rajičić, Bratislav
PY  - 2006
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/575
PB  - Kluwer Academic Publishers
C3  - Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere
T1  - Structure integrity of pressure vesels repair welding joints
EP  - 1084
SP  - 1083
DO  - 10.1007/1-4020-4972-2_537
ER  - 

@conference{
author = "Zeravčić-Šijački, Vera and Bakić, Gordana and Đukić, Miloš and Rajičić, Bratislav",
year = "2006",
publisher = "Kluwer Academic Publishers",
journal = "Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere",
title = "Structure integrity of pressure vesels repair welding joints",
pages = "1084-1083",
doi = "10.1007/1-4020-4972-2_537"
}

Zeravčić-Šijački, V., Bakić, G., Đukić, M.,& Rajičić, B.. (2006). Structure integrity of pressure vesels repair welding joints. in Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere
Kluwer Academic Publishers., 1083-1084.
https://doi.org/10.1007/1-4020-4972-2_537

Zeravčić-Šijački V, Bakić G, Đukić M, Rajičić B. Structure integrity of pressure vesels repair welding joints. in Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere. 2006;:1083-1084.
doi:10.1007/1-4020-4972-2_537 .

Zeravčić-Šijački, Vera, Bakić, Gordana, Đukić, Miloš, Rajičić, Bratislav, "Structure integrity of pressure vesels repair welding joints" in Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere (2006):1083-1084,
https://doi.org/10.1007/1-4020-4972-2_537 . .

TY  - CONF
AU  - Zeravčić-Šijački, Vera
AU  - Đukić, Miloš
AU  - Bakić, Gordana
AU  - Anđelić, Biljana
AU  - Rajičić, Bratislav
PY  - 2006
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/574
PB  - Kluwer Academic Publishers
C3  - Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere
T1  - Case study of supporting tubes failure
EP  - 1082
SP  - 1081
DO  - 10.1007/1-4020-4972-2_536
ER  - 

@conference{
author = "Zeravčić-Šijački, Vera and Đukić, Miloš and Bakić, Gordana and Anđelić, Biljana and Rajičić, Bratislav",
year = "2006",
publisher = "Kluwer Academic Publishers",
journal = "Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere",
title = "Case study of supporting tubes failure",
pages = "1082-1081",
doi = "10.1007/1-4020-4972-2_536"
}

Zeravčić-Šijački, V., Đukić, M., Bakić, G., Anđelić, B.,& Rajičić, B.. (2006). Case study of supporting tubes failure. in Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere
Kluwer Academic Publishers., 1081-1082.
https://doi.org/10.1007/1-4020-4972-2_536

Zeravčić-Šijački V, Đukić M, Bakić G, Anđelić B, Rajičić B. Case study of supporting tubes failure. in Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere. 2006;:1081-1082.
doi:10.1007/1-4020-4972-2_536 .

Zeravčić-Šijački, Vera, Đukić, Miloš, Bakić, Gordana, Anđelić, Biljana, Rajičić, Bratislav, "Case study of supporting tubes failure" in Fracture of Nano and Engineering Materials and Structures - Proceedings of the 16th European Confere (2006):1081-1082,
https://doi.org/10.1007/1-4020-4972-2_536 . .

TY  - CONF
AU  - Anđelić, Biljana
AU  - Zeravčić-Šijački, Vera
AU  - Đukić, Miloš
AU  - Bakić, Gordana
PY  - 2005
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/468
AB  - Constant demands for quality improvement of high-speed steels have contributed to the prolonged importance of tests, such as test in structural changes and properties derived from the applied heat treatment. Generally, tools from high-speed steel are treated by multiple tempering after quenching in order to reduce amount of retained austenite and value of internal stresses to the lowest level. A review of literature shows that processes taking place during the first tempering have been studied comprehensively and in great detail while very little attention has been paid to testing structural changes in the succeeding tempering cycles. Having this in mind, the differential dilatometric method has been used to test the influences of quenching temperature (1170-1230°C), tempering temperature (540-605°C), and the number (1 to 5) and tempering time, on the process of destabilization of retained austenite at circumstances of multiple continuous tempering of quenched W-Mo-V high-speed steel. The acquired results have contributed to the conviction that the customary regime of tempering for this type of high-speed steel could be rationally modified. We emphasize that the change in tendency of the dilatometric cooling curve in the austenitic-martensitic transformation region is the result of self-tempering of secondary martensite. The explanation proposed in literature for this dilatometric effect is from our point of view totally incorrect.
C3  - 11th International Conference on Fracture 2005, ICF11
T1  - Destabilization of retained austenite during multiple tempering of high-speed W-Mo-V steel
EP  - 3919
SP  - 3914
VL  - 5
UR  - https://hdl.handle.net/21.15107/rcub_machinery_468
ER  - 

@conference{
author = "Anđelić, Biljana and Zeravčić-Šijački, Vera and Đukić, Miloš and Bakić, Gordana",
year = "2005",
abstract = "Constant demands for quality improvement of high-speed steels have contributed to the prolonged importance of tests, such as test in structural changes and properties derived from the applied heat treatment. Generally, tools from high-speed steel are treated by multiple tempering after quenching in order to reduce amount of retained austenite and value of internal stresses to the lowest level. A review of literature shows that processes taking place during the first tempering have been studied comprehensively and in great detail while very little attention has been paid to testing structural changes in the succeeding tempering cycles. Having this in mind, the differential dilatometric method has been used to test the influences of quenching temperature (1170-1230°C), tempering temperature (540-605°C), and the number (1 to 5) and tempering time, on the process of destabilization of retained austenite at circumstances of multiple continuous tempering of quenched W-Mo-V high-speed steel. The acquired results have contributed to the conviction that the customary regime of tempering for this type of high-speed steel could be rationally modified. We emphasize that the change in tendency of the dilatometric cooling curve in the austenitic-martensitic transformation region is the result of self-tempering of secondary martensite. The explanation proposed in literature for this dilatometric effect is from our point of view totally incorrect.",
journal = "11th International Conference on Fracture 2005, ICF11",
title = "Destabilization of retained austenite during multiple tempering of high-speed W-Mo-V steel",
pages = "3919-3914",
volume = "5",
url = "https://hdl.handle.net/21.15107/rcub_machinery_468"
}

Anđelić, B., Zeravčić-Šijački, V., Đukić, M.,& Bakić, G.. (2005). Destabilization of retained austenite during multiple tempering of high-speed W-Mo-V steel. in 11th International Conference on Fracture 2005, ICF11, 5, 3914-3919.
https://hdl.handle.net/21.15107/rcub_machinery_468

Anđelić B, Zeravčić-Šijački V, Đukić M, Bakić G. Destabilization of retained austenite during multiple tempering of high-speed W-Mo-V steel. in 11th International Conference on Fracture 2005, ICF11. 2005;5:3914-3919.
https://hdl.handle.net/21.15107/rcub_machinery_468 .

Anđelić, Biljana, Zeravčić-Šijački, Vera, Đukić, Miloš, Bakić, Gordana, "Destabilization of retained austenite during multiple tempering of high-speed W-Mo-V steel" in 11th International Conference on Fracture 2005, ICF11, 5 (2005):3914-3919,
https://hdl.handle.net/21.15107/rcub_machinery_468 .

TY  - CONF
AU  - Bakić, Gordana
AU  - Zeravčić-Šijački, Vera
AU  - Radović, M.
PY  - 2005
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/551
AB  - The decreases of creep resistance can be in most cases, attributed to microstructural degradation in CrMoV steels, such as perlite degradation, carbides precipitation, etc. It is a usual practice to employ a statistical approach to define relationship between some parameters that characterize microstructural degradation and changes in creep resistance of the material. However, statistical analysis of the physically significant parameters that characterize microstructural degradation is usually not straightforward because of the lack and/or unreliability of experimental creep data for most of the materials. In this paper we propose a new approach that is based on determination of the materials strength using modified kinetic theory (based on Zurkov relation). The elementary destruction act is entirely defined in this model from physical point of view, as a result of thermal fluctuations of the atoms. This approach based on the microstructural parameters and modified kinetic theory of strength is used to estimate time to failure of the CrMoV steels in high-temperature creep conditions.
PB  - DEStech Publications Inc.
C3  - Proceedings - ECCC Creep Conference: Creep and Fracture in High Temperature Components - Design and
T1  - Estimation of the failure time for low-carbon CrMoV steels in creep condition using modified kinetic theory based on microstructural parameters
EP  - 243
SP  - 235
VL  - 2005
UR  - https://hdl.handle.net/21.15107/rcub_machinery_551
ER  - 

@conference{
author = "Bakić, Gordana and Zeravčić-Šijački, Vera and Radović, M.",
year = "2005",
abstract = "The decreases of creep resistance can be in most cases, attributed to microstructural degradation in CrMoV steels, such as perlite degradation, carbides precipitation, etc. It is a usual practice to employ a statistical approach to define relationship between some parameters that characterize microstructural degradation and changes in creep resistance of the material. However, statistical analysis of the physically significant parameters that characterize microstructural degradation is usually not straightforward because of the lack and/or unreliability of experimental creep data for most of the materials. In this paper we propose a new approach that is based on determination of the materials strength using modified kinetic theory (based on Zurkov relation). The elementary destruction act is entirely defined in this model from physical point of view, as a result of thermal fluctuations of the atoms. This approach based on the microstructural parameters and modified kinetic theory of strength is used to estimate time to failure of the CrMoV steels in high-temperature creep conditions.",
publisher = "DEStech Publications Inc.",
journal = "Proceedings - ECCC Creep Conference: Creep and Fracture in High Temperature Components - Design and",
title = "Estimation of the failure time for low-carbon CrMoV steels in creep condition using modified kinetic theory based on microstructural parameters",
pages = "243-235",
volume = "2005",
url = "https://hdl.handle.net/21.15107/rcub_machinery_551"
}

Bakić, G., Zeravčić-Šijački, V.,& Radović, M.. (2005). Estimation of the failure time for low-carbon CrMoV steels in creep condition using modified kinetic theory based on microstructural parameters. in Proceedings - ECCC Creep Conference: Creep and Fracture in High Temperature Components - Design and
DEStech Publications Inc.., 2005, 235-243.
https://hdl.handle.net/21.15107/rcub_machinery_551

Bakić G, Zeravčić-Šijački V, Radović M. Estimation of the failure time for low-carbon CrMoV steels in creep condition using modified kinetic theory based on microstructural parameters. in Proceedings - ECCC Creep Conference: Creep and Fracture in High Temperature Components - Design and. 2005;2005:235-243.
https://hdl.handle.net/21.15107/rcub_machinery_551 .

Bakić, Gordana, Zeravčić-Šijački, Vera, Radović, M., "Estimation of the failure time for low-carbon CrMoV steels in creep condition using modified kinetic theory based on microstructural parameters" in Proceedings - ECCC Creep Conference: Creep and Fracture in High Temperature Components - Design and, 2005 (2005):235-243,
https://hdl.handle.net/21.15107/rcub_machinery_551 .

TY  - CONF
AU  - Bakić, Gordana
AU  - Zeravčić-Šijački, Vera
AU  - Đukić, Miloš
AU  - Milanović, D.
AU  - Anđelić, Biljana
PY  - 2005
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/483
AB  - Structural integrity of power plant component is usually estimate by its residual service life. Input data for component residual life estimation exposed to high-temperature creep is the creep strength of material (time dependent strength), after particular service period. Creep strength is usually obtained by statistical treatment of experimental data, and it decreases during service time due to degradation of microstructure. Since the creep resistance decreases with time due to microstructure degradation, it is essential for practice to use microstructural parameters in order to define statistically the changes in the creep resistance, which in turn enables to follow the physical significance of these changes. Due to a considerable scatter in the creep data, treatment by statistical analysis of the physically significant parameters is a problem that, to date has not been satisfactorily solved. One of attempt to overcome the lack of all data, which were required for previous analyses and estimation of service resources/service life, is done in this paper. Kinetic process has to be defined by the rate of process or by time for which such process will cause the rupture, instead of creep strength. Thus, the time to fracture of the component subjected to a high-temperature creep is determined due the kinetic theory of strength (model Zurkov) and using the microstructural parameters as an input data.
C3  - 11th International Conference on Fracture 2005, ICF11
T1  - Model for time-to-fracture determination of low-alloyed steel under creep conditions
EP  - 3066
SP  - 3061
VL  - 4
UR  - https://hdl.handle.net/21.15107/rcub_machinery_483
ER  - 

@conference{
author = "Bakić, Gordana and Zeravčić-Šijački, Vera and Đukić, Miloš and Milanović, D. and Anđelić, Biljana",
year = "2005",
abstract = "Structural integrity of power plant component is usually estimate by its residual service life. Input data for component residual life estimation exposed to high-temperature creep is the creep strength of material (time dependent strength), after particular service period. Creep strength is usually obtained by statistical treatment of experimental data, and it decreases during service time due to degradation of microstructure. Since the creep resistance decreases with time due to microstructure degradation, it is essential for practice to use microstructural parameters in order to define statistically the changes in the creep resistance, which in turn enables to follow the physical significance of these changes. Due to a considerable scatter in the creep data, treatment by statistical analysis of the physically significant parameters is a problem that, to date has not been satisfactorily solved. One of attempt to overcome the lack of all data, which were required for previous analyses and estimation of service resources/service life, is done in this paper. Kinetic process has to be defined by the rate of process or by time for which such process will cause the rupture, instead of creep strength. Thus, the time to fracture of the component subjected to a high-temperature creep is determined due the kinetic theory of strength (model Zurkov) and using the microstructural parameters as an input data.",
journal = "11th International Conference on Fracture 2005, ICF11",
title = "Model for time-to-fracture determination of low-alloyed steel under creep conditions",
pages = "3066-3061",
volume = "4",
url = "https://hdl.handle.net/21.15107/rcub_machinery_483"
}

Bakić, G., Zeravčić-Šijački, V., Đukić, M., Milanović, D.,& Anđelić, B.. (2005). Model for time-to-fracture determination of low-alloyed steel under creep conditions. in 11th International Conference on Fracture 2005, ICF11, 4, 3061-3066.
https://hdl.handle.net/21.15107/rcub_machinery_483

Bakić G, Zeravčić-Šijački V, Đukić M, Milanović D, Anđelić B. Model for time-to-fracture determination of low-alloyed steel under creep conditions. in 11th International Conference on Fracture 2005, ICF11. 2005;4:3061-3066.
https://hdl.handle.net/21.15107/rcub_machinery_483 .

Bakić, Gordana, Zeravčić-Šijački, Vera, Đukić, Miloš, Milanović, D., Anđelić, Biljana, "Model for time-to-fracture determination of low-alloyed steel under creep conditions" in 11th International Conference on Fracture 2005, ICF11, 4 (2005):3061-3066,
https://hdl.handle.net/21.15107/rcub_machinery_483 .