TY  - JOUR
AU  - Vencl, Aleksandar
AU  - Rajković, Viseslava
AU  - Zivić, Fatima
AU  - Mitrović, Slobodan
AU  - Cvijović-Alagić, Ivana
AU  - Jovanović, Milan T.
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1711
AB  - Three copper-based alloys, i.e. two composites reinforced with Al2O3 particles and fabricated through PM route and Cu-Cr-Zr alloy processed by the vacuum melting and casting technique were the object of this investigation. Light microscope, scanning electron microscope (SEM) equipped with electron X-ray spectrometer (EDS) and transmission electron microscope (TEM) were used for microstructural characterization. The ball-on-disc nanotribometer served for wear and friction tests applying low sliding speeds (6, 8 and 10 mm/s) at constant load (1 N). The objective of the paper was to investigate the effect of different processing techniques on microstructure, thermal stability and the tribological characteristics of composites and copper ingot alloy. Nano-sized Al2O3 particles (less than 100 nm in size) are present not only in the copper matrix of Cu-2.5 wt.% Al composite, obtained by internal oxidation, but they are also formed at the grain boundaries preventing the grain growth and providing very small grain size. During the high temperature annealing (in the range 300-950 degrees C) composites behaved much better than the ingot alloy. The highest thermal stability showed Cu-2.5 wt.% Al composite. The pinning effect of nano-sized Al2O3 particles prevents the grain growth slowing down recrystallization of this composite up to 900 degrees C. Micro-sized Al2O3 particles in Cu-5 wt.% Al2O3 composite, processed by mechanical annealing, are not effective in preventing dislocation motion and the grain growth, whereas microstructure of Cu-0.4 wt.% Cr-0.08 wt.% Zr ingot alloy was completely recrystallized around 550 degrees C. Cu-2.5 wt.% Al composite showed the best wear resistance, approximately 2.5 times higher than that of Cu-5 wt.% Al2O3 composite. High hardness and nano-sized Al2O3 particles size combined with the fine-grain structure are the main parameters leading to the improved wear resistance of the Cu-2.5Al composite.
PB  - Elsevier Science Bv, Amsterdam
T2  - Applied Surface Science
T1  - The effect of processing techniques on microstructural and tribological properties of copper-based alloys
EP  - 654
SP  - 646
VL  - 280
DO  - 10.1016/j.apsusc.2013.05.039
ER  - 

@article{
author = "Vencl, Aleksandar and Rajković, Viseslava and Zivić, Fatima and Mitrović, Slobodan and Cvijović-Alagić, Ivana and Jovanović, Milan T.",
year = "2013",
abstract = "Three copper-based alloys, i.e. two composites reinforced with Al2O3 particles and fabricated through PM route and Cu-Cr-Zr alloy processed by the vacuum melting and casting technique were the object of this investigation. Light microscope, scanning electron microscope (SEM) equipped with electron X-ray spectrometer (EDS) and transmission electron microscope (TEM) were used for microstructural characterization. The ball-on-disc nanotribometer served for wear and friction tests applying low sliding speeds (6, 8 and 10 mm/s) at constant load (1 N). The objective of the paper was to investigate the effect of different processing techniques on microstructure, thermal stability and the tribological characteristics of composites and copper ingot alloy. Nano-sized Al2O3 particles (less than 100 nm in size) are present not only in the copper matrix of Cu-2.5 wt.% Al composite, obtained by internal oxidation, but they are also formed at the grain boundaries preventing the grain growth and providing very small grain size. During the high temperature annealing (in the range 300-950 degrees C) composites behaved much better than the ingot alloy. The highest thermal stability showed Cu-2.5 wt.% Al composite. The pinning effect of nano-sized Al2O3 particles prevents the grain growth slowing down recrystallization of this composite up to 900 degrees C. Micro-sized Al2O3 particles in Cu-5 wt.% Al2O3 composite, processed by mechanical annealing, are not effective in preventing dislocation motion and the grain growth, whereas microstructure of Cu-0.4 wt.% Cr-0.08 wt.% Zr ingot alloy was completely recrystallized around 550 degrees C. Cu-2.5 wt.% Al composite showed the best wear resistance, approximately 2.5 times higher than that of Cu-5 wt.% Al2O3 composite. High hardness and nano-sized Al2O3 particles size combined with the fine-grain structure are the main parameters leading to the improved wear resistance of the Cu-2.5Al composite.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Applied Surface Science",
title = "The effect of processing techniques on microstructural and tribological properties of copper-based alloys",
pages = "654-646",
volume = "280",
doi = "10.1016/j.apsusc.2013.05.039"
}

Vencl, A., Rajković, V., Zivić, F., Mitrović, S., Cvijović-Alagić, I.,& Jovanović, M. T.. (2013). The effect of processing techniques on microstructural and tribological properties of copper-based alloys. in Applied Surface Science
Elsevier Science Bv, Amsterdam., 280, 646-654.
https://doi.org/10.1016/j.apsusc.2013.05.039

Vencl A, Rajković V, Zivić F, Mitrović S, Cvijović-Alagić I, Jovanović MT. The effect of processing techniques on microstructural and tribological properties of copper-based alloys. in Applied Surface Science. 2013;280:646-654.
doi:10.1016/j.apsusc.2013.05.039 .

Vencl, Aleksandar, Rajković, Viseslava, Zivić, Fatima, Mitrović, Slobodan, Cvijović-Alagić, Ivana, Jovanović, Milan T., "The effect of processing techniques on microstructural and tribological properties of copper-based alloys" in Applied Surface Science, 280 (2013):646-654,
https://doi.org/10.1016/j.apsusc.2013.05.039 . .

TY  - CONF
AU  - Božić, D.
AU  - Devečerski, A.
AU  - Erić, Olivera
AU  - Rajković, Viseslava
AU  - Gnjidić, Ž.
PY  - 2004
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/393
AB  - Composite materials based on the CW67 alloy (Al base matrix) and volume fraction of 15 pet of SiC particles in two nominal sizes (0.7 μm and 33 μm) have been produced by hot pressing. The fracture behavior of the composite and the monolithic alloy was studied under uniaxial compressive loading at room temperature. Detailed microstructure characterization of the hot pressed monolithic alloy and composite has been evaluated by optical and scanning electron microscopy (SEM). The large reinforcement particles and the presence of SiC agglomerates could have a major effect on the mechanical properties of the composite materials.
PB  - Trans Tech Publications Ltd
C3  - Materials Science Forum
T1  - Effects of structure characteristics on mechanical properties of aluminum alloy matrix composites
EP  - 520
SP  - 515
VL  - 453-454
DO  - 10.4028/www.scientific.net/msf.453-454.515
ER  - 

@conference{
author = "Božić, D. and Devečerski, A. and Erić, Olivera and Rajković, Viseslava and Gnjidić, Ž.",
year = "2004",
abstract = "Composite materials based on the CW67 alloy (Al base matrix) and volume fraction of 15 pet of SiC particles in two nominal sizes (0.7 μm and 33 μm) have been produced by hot pressing. The fracture behavior of the composite and the monolithic alloy was studied under uniaxial compressive loading at room temperature. Detailed microstructure characterization of the hot pressed monolithic alloy and composite has been evaluated by optical and scanning electron microscopy (SEM). The large reinforcement particles and the presence of SiC agglomerates could have a major effect on the mechanical properties of the composite materials.",
publisher = "Trans Tech Publications Ltd",
journal = "Materials Science Forum",
title = "Effects of structure characteristics on mechanical properties of aluminum alloy matrix composites",
pages = "520-515",
volume = "453-454",
doi = "10.4028/www.scientific.net/msf.453-454.515"
}

Božić, D., Devečerski, A., Erić, O., Rajković, V.,& Gnjidić, Ž.. (2004). Effects of structure characteristics on mechanical properties of aluminum alloy matrix composites. in Materials Science Forum
Trans Tech Publications Ltd., 453-454, 515-520.
https://doi.org/10.4028/www.scientific.net/msf.453-454.515

Božić D, Devečerski A, Erić O, Rajković V, Gnjidić Ž. Effects of structure characteristics on mechanical properties of aluminum alloy matrix composites. in Materials Science Forum. 2004;453-454:515-520.
doi:10.4028/www.scientific.net/msf.453-454.515 .

Božić, D., Devečerski, A., Erić, Olivera, Rajković, Viseslava, Gnjidić, Ž., "Effects of structure characteristics on mechanical properties of aluminum alloy matrix composites" in Materials Science Forum, 453-454 (2004):515-520,
https://doi.org/10.4028/www.scientific.net/msf.453-454.515 . .

TY  - JOUR
AU  - Rajković, Viseslava
AU  - Erić, Olivera
AU  - Božić, D.
AU  - Mitkov, M
AU  - Romhanji, E
PY  - 2004
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/455
AB  - The copper matrix has been dispersion strengthened with 3wt. %Al2O3 by mechanical alloying. Commercial alumina powder with an average particle size of 0.751 mum was used for alloying. The mechanical alloying process was performed in a planetary ball mill up to 20h in air. After milling all powders were treated in H-2 at 400(degrees)C for 1h, and finally hot pressing was used for compaction (800degreesC, 3h, Ar). Structure observations revealed a lamellar structure (Al2O3 particles largely restricted to interlamellar planes between adjacent copper lamellae) accompanied also by structure refinement. These structural changes were mostly completed in the early stage of milling, and retained after compaction. Micro. hardness was found to progressively increase with milling time. So, after 5h of milling the micro hardness of the Cu+3twt%Al2O3 compact was 1540MPa, i.e. 2.5 times greater than for the as-received electrolytic copper powder (638MPa) compacted under identical conditions, while after 20h of milling it was 2370 MPa. However, after exposing the tested compact at 800degreesC up to 5h, the achieved hardening effect vanished.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying
EP  - 211
IS  - 3
SP  - 205
VL  - 36
DO  - 10.2298/SOS0403205R
ER  - 

@article{
author = "Rajković, Viseslava and Erić, Olivera and Božić, D. and Mitkov, M and Romhanji, E",
year = "2004",
abstract = "The copper matrix has been dispersion strengthened with 3wt. %Al2O3 by mechanical alloying. Commercial alumina powder with an average particle size of 0.751 mum was used for alloying. The mechanical alloying process was performed in a planetary ball mill up to 20h in air. After milling all powders were treated in H-2 at 400(degrees)C for 1h, and finally hot pressing was used for compaction (800degreesC, 3h, Ar). Structure observations revealed a lamellar structure (Al2O3 particles largely restricted to interlamellar planes between adjacent copper lamellae) accompanied also by structure refinement. These structural changes were mostly completed in the early stage of milling, and retained after compaction. Micro. hardness was found to progressively increase with milling time. So, after 5h of milling the micro hardness of the Cu+3twt%Al2O3 compact was 1540MPa, i.e. 2.5 times greater than for the as-received electrolytic copper powder (638MPa) compacted under identical conditions, while after 20h of milling it was 2370 MPa. However, after exposing the tested compact at 800degreesC up to 5h, the achieved hardening effect vanished.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying",
pages = "211-205",
number = "3",
volume = "36",
doi = "10.2298/SOS0403205R"
}

Rajković, V., Erić, O., Božić, D., Mitkov, M.,& Romhanji, E.. (2004). Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 36(3), 205-211.
https://doi.org/10.2298/SOS0403205R

Rajković V, Erić O, Božić D, Mitkov M, Romhanji E. Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying. in Science of Sintering. 2004;36(3):205-211.
doi:10.2298/SOS0403205R .

Rajković, Viseslava, Erić, Olivera, Božić, D., Mitkov, M, Romhanji, E, "Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying" in Science of Sintering, 36, no. 3 (2004):205-211,
https://doi.org/10.2298/SOS0403205R . .