TY  - JOUR
AU  - Vencl, Aleksandar
AU  - Bobić, Ilija
AU  - Kandeva, Mara
AU  - Karastoyanov, Dimitar
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4312
AB  - This paper presents a short summary of the researches conducted in past few years concerning the metal matrix composites with different matrix material, different reinforcing/alloying elements, and obtained by different processing techniques. The results are classified into three groups according to the matrix material. In the first group are the results for microcomposites with AlSi7Mg matrix alloy obtained by compocasting method. These results cover the influences of amount and size of reinforcement (Al2O3), and the influence of type of reinforcement (Al2O3, SiC and SiC with graphite addition). In the second group are the results for nanocomposites with ZnAl25Si matrix alloy obtained by casting and compocasting method. These results cover the influences of silicon and strontium addition percentage, and the influences of strontium and/or Al2O3 nanoparticles addition. In the third group are the results for micro- and nanocomposites with Cu matrix obtained by powder metallurgy technology (preceded by mechanical alloying and/or internal oxidation). These results cover the influence of size of reinforcement (Al2O3) on the macroscale (composite properties), and the same influence on the nanoscale (only the matrix properties).
PB  - Sofia : Technical University
T2  - Tribological Journal BULTRIB
T1  - Tribology of metal matrix micro- and nanocomposites
EP  - 19
SP  - 10
VL  - 5
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4312
ER  - 

@article{
author = "Vencl, Aleksandar and Bobić, Ilija and Kandeva, Mara and Karastoyanov, Dimitar",
year = "2015",
abstract = "This paper presents a short summary of the researches conducted in past few years concerning the metal matrix composites with different matrix material, different reinforcing/alloying elements, and obtained by different processing techniques. The results are classified into three groups according to the matrix material. In the first group are the results for microcomposites with AlSi7Mg matrix alloy obtained by compocasting method. These results cover the influences of amount and size of reinforcement (Al2O3), and the influence of type of reinforcement (Al2O3, SiC and SiC with graphite addition). In the second group are the results for nanocomposites with ZnAl25Si matrix alloy obtained by casting and compocasting method. These results cover the influences of silicon and strontium addition percentage, and the influences of strontium and/or Al2O3 nanoparticles addition. In the third group are the results for micro- and nanocomposites with Cu matrix obtained by powder metallurgy technology (preceded by mechanical alloying and/or internal oxidation). These results cover the influence of size of reinforcement (Al2O3) on the macroscale (composite properties), and the same influence on the nanoscale (only the matrix properties).",
publisher = "Sofia : Technical University",
journal = "Tribological Journal BULTRIB",
title = "Tribology of metal matrix micro- and nanocomposites",
pages = "19-10",
volume = "5",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4312"
}

Vencl, A., Bobić, I., Kandeva, M.,& Karastoyanov, D.. (2015). Tribology of metal matrix micro- and nanocomposites. in Tribological Journal BULTRIB
Sofia : Technical University., 5, 10-19.
https://hdl.handle.net/21.15107/rcub_machinery_4312

Vencl A, Bobić I, Kandeva M, Karastoyanov D. Tribology of metal matrix micro- and nanocomposites. in Tribological Journal BULTRIB. 2015;5:10-19.
https://hdl.handle.net/21.15107/rcub_machinery_4312 .

Vencl, Aleksandar, Bobić, Ilija, Kandeva, Mara, Karastoyanov, Dimitar, "Tribology of metal matrix micro- and nanocomposites" in Tribological Journal BULTRIB, 5 (2015):10-19,
https://hdl.handle.net/21.15107/rcub_machinery_4312 .

TY  - JOUR
AU  - Vencl, Aleksandar
AU  - Jakimovska, Kristina
AU  - Ivanova, Boryan
AU  - Ružić, Jovana
AU  - Simeonov, Simeon
AU  - Kandeva, Mara
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4334
AB  - The aim of this study was to examine the static and kinetic friction of electroless Ni coatings of different surface roughening, in unlubricated contact with various counter-body materials. In particular, difference between static and kinetic coefficients of friction was analysed. The Ni coatings deposition was done with electroless plating process. Samples of electroless Ni coatings without and with SiC nanoparticles were heat treated at 300 °С for 6 hours. The microstructure of all samples was characterized by optical microscopy. Microhardness of samples and counter-bodies were also examined. The static and kinetic coefficients of friction was measured for each coating with initial and working surface roughness. Three typical materials used in industry were chosen as a counter-body material. The possibility of stick-slip occurrence was analysed through the static and kinetic coefficients of friction difference. Obtained results show that coatings hardness has strong influence on coefficient of friction, and that slip-stick phenomenon is unlikely to occur, since the differences between static and kinetic coefficients of friction are small. The SiC nanoparticles were added to Ni coating in order to improve the abrasive wear resistance. In the same time, presence of SiC nanoparticles slightly increases the coefficient of friction in unlubricated conditions. Obtained results showed that surface roughness does not have major influence on the coefficient of friction of tested coatings, and that coatings hardness is more influential. The SiC nanoparticles were added to standard electroless Ni coating, and their properties are investigated. Heat treatment was applied to achieve crystalline structure and to improve mechanical and tribological properties. Coefficient of friction testing was performed by simply and easy to operate test rig.
T2  - Journal of Achievements in Materials and Manufacturing Engineering
T1  - Static and kinetic friction of electroless Ni composite coatings
EP  - 21
IS  - 1
SP  - 13
VL  - 70
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4334
ER  - 

@article{
author = "Vencl, Aleksandar and Jakimovska, Kristina and Ivanova, Boryan and Ružić, Jovana and Simeonov, Simeon and Kandeva, Mara",
year = "2015",
abstract = "The aim of this study was to examine the static and kinetic friction of electroless Ni coatings of different surface roughening, in unlubricated contact with various counter-body materials. In particular, difference between static and kinetic coefficients of friction was analysed. The Ni coatings deposition was done with electroless plating process. Samples of electroless Ni coatings without and with SiC nanoparticles were heat treated at 300 °С for 6 hours. The microstructure of all samples was characterized by optical microscopy. Microhardness of samples and counter-bodies were also examined. The static and kinetic coefficients of friction was measured for each coating with initial and working surface roughness. Three typical materials used in industry were chosen as a counter-body material. The possibility of stick-slip occurrence was analysed through the static and kinetic coefficients of friction difference. Obtained results show that coatings hardness has strong influence on coefficient of friction, and that slip-stick phenomenon is unlikely to occur, since the differences between static and kinetic coefficients of friction are small. The SiC nanoparticles were added to Ni coating in order to improve the abrasive wear resistance. In the same time, presence of SiC nanoparticles slightly increases the coefficient of friction in unlubricated conditions. Obtained results showed that surface roughness does not have major influence on the coefficient of friction of tested coatings, and that coatings hardness is more influential. The SiC nanoparticles were added to standard electroless Ni coating, and their properties are investigated. Heat treatment was applied to achieve crystalline structure and to improve mechanical and tribological properties. Coefficient of friction testing was performed by simply and easy to operate test rig.",
journal = "Journal of Achievements in Materials and Manufacturing Engineering",
title = "Static and kinetic friction of electroless Ni composite coatings",
pages = "21-13",
number = "1",
volume = "70",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4334"
}

Vencl, A., Jakimovska, K., Ivanova, B., Ružić, J., Simeonov, S.,& Kandeva, M.. (2015). Static and kinetic friction of electroless Ni composite coatings. in Journal of Achievements in Materials and Manufacturing Engineering, 70(1), 13-21.
https://hdl.handle.net/21.15107/rcub_machinery_4334

Vencl A, Jakimovska K, Ivanova B, Ružić J, Simeonov S, Kandeva M. Static and kinetic friction of electroless Ni composite coatings. in Journal of Achievements in Materials and Manufacturing Engineering. 2015;70(1):13-21.
https://hdl.handle.net/21.15107/rcub_machinery_4334 .

Vencl, Aleksandar, Jakimovska, Kristina, Ivanova, Boryan, Ružić, Jovana, Simeonov, Simeon, Kandeva, Mara, "Static and kinetic friction of electroless Ni composite coatings" in Journal of Achievements in Materials and Manufacturing Engineering, 70, no. 1 (2015):13-21,
https://hdl.handle.net/21.15107/rcub_machinery_4334 .

TY  - CONF
AU  - Kandeva, Aleksandar
AU  - Vencl, Aleksandar
AU  - Assenova, Emilia
AU  - Karastoyanov, Dimitar
AU  - Grozdanova, Tinka
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4347
AB  - Using the disk-abrasive roller test rig, wear behaviour of chemical Ni coatings containing boron nitride nanoparticles has been studied. The coatings were deposited by means of EFTOM-Ni technology method patented at the Technical University - Sofia. Comparative study has been done of wear resistance of the heat treated (heating during 6 h at 300˚C) and as deposited (no additional heat treatment) coatings, correspondingly with contents of particles of 10 μm averaged size and without nanoparticles addition.
C3  - Proceedings of the 11th International Conference in Manufacturing Engineering THE "A" Coatings
T1  - Abrasive wear of chemical nickel coatings with boron nitride nano-particles
EP  - 325
SP  - 319
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4347
ER  - 

@conference{
author = "Kandeva, Aleksandar and Vencl, Aleksandar and Assenova, Emilia and Karastoyanov, Dimitar and Grozdanova, Tinka",
year = "2014",
abstract = "Using the disk-abrasive roller test rig, wear behaviour of chemical Ni coatings containing boron nitride nanoparticles has been studied. The coatings were deposited by means of EFTOM-Ni technology method patented at the Technical University - Sofia. Comparative study has been done of wear resistance of the heat treated (heating during 6 h at 300˚C) and as deposited (no additional heat treatment) coatings, correspondingly with contents of particles of 10 μm averaged size and without nanoparticles addition.",
journal = "Proceedings of the 11th International Conference in Manufacturing Engineering THE "A" Coatings",
title = "Abrasive wear of chemical nickel coatings with boron nitride nano-particles",
pages = "325-319",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4347"
}

Kandeva, A., Vencl, A., Assenova, E., Karastoyanov, D.,& Grozdanova, T.. (2014). Abrasive wear of chemical nickel coatings with boron nitride nano-particles. in Proceedings of the 11th International Conference in Manufacturing Engineering THE "A" Coatings, 319-325.
https://hdl.handle.net/21.15107/rcub_machinery_4347

Kandeva A, Vencl A, Assenova E, Karastoyanov D, Grozdanova T. Abrasive wear of chemical nickel coatings with boron nitride nano-particles. in Proceedings of the 11th International Conference in Manufacturing Engineering THE "A" Coatings. 2014;:319-325.
https://hdl.handle.net/21.15107/rcub_machinery_4347 .

Kandeva, Aleksandar, Vencl, Aleksandar, Assenova, Emilia, Karastoyanov, Dimitar, Grozdanova, Tinka, "Abrasive wear of chemical nickel coatings with boron nitride nano-particles" in Proceedings of the 11th International Conference in Manufacturing Engineering THE "A" Coatings (2014):319-325,
https://hdl.handle.net/21.15107/rcub_machinery_4347 .