TY  - JOUR
AU  - Vencl, Aleksandar
AU  - Bobić, Ilija
AU  - Stanković, Miloš
AU  - Hvizdoš, Pavol
AU  - Bobić, Biljana M.
AU  - Stojanović, Blaža
AU  - Franek, Friedrich
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8829
AB  - Metal matrix composites are very inhomogeneous materials, and their properties depend on various parameters (production process, constituents, their interfaces, etc.). The influence of SiC microparticles (40 mu m) reinforcement and graphite macroparticles (200-800 mu m) addition on the mechanical properties of Al-Si A356 alloy, produced by compocasting, has been assessed using macro- and nanoscale measurements of hardness and modulus of elasticity. The Al makes over 90 wt% of the A356 alloy, so the nanoscale measurements were performed on different alpha phase regions on each material (core of alpha phase, eutectic alpha phase, and alpha phase near the phase boundaries alpha phase/secondary phases). The results showed that there is no direct correlation between mechanical properties on macro- and nanoscale. The nanoscale results also showed that the secondary phases (SiC and graphite particles) can have significant effect on the mechanical properties on the atomic level, i.e. in the alpha phase regions very close to the secondary phases.
T2  - Journal of the Brazilian Society of Mechanical Sciences and Engineering
T1  - Influence of secondary phases in A356 MMCs on their mechanical properties at macro- and nanoscale
VL  - 42
IS  - 3
SP  - 115
DO  - 10.1007/s40430-020-2197-6
ER  - 

@article{
author = "Vencl, Aleksandar and Bobić, Ilija and Stanković, Miloš and Hvizdoš, Pavol and Bobić, Biljana M. and Stojanović, Blaža and Franek, Friedrich",
year = "2020",
abstract = "Metal matrix composites are very inhomogeneous materials, and their properties depend on various parameters (production process, constituents, their interfaces, etc.). The influence of SiC microparticles (40 mu m) reinforcement and graphite macroparticles (200-800 mu m) addition on the mechanical properties of Al-Si A356 alloy, produced by compocasting, has been assessed using macro- and nanoscale measurements of hardness and modulus of elasticity. The Al makes over 90 wt% of the A356 alloy, so the nanoscale measurements were performed on different alpha phase regions on each material (core of alpha phase, eutectic alpha phase, and alpha phase near the phase boundaries alpha phase/secondary phases). The results showed that there is no direct correlation between mechanical properties on macro- and nanoscale. The nanoscale results also showed that the secondary phases (SiC and graphite particles) can have significant effect on the mechanical properties on the atomic level, i.e. in the alpha phase regions very close to the secondary phases.",
journal = "Journal of the Brazilian Society of Mechanical Sciences and Engineering",
title = "Influence of secondary phases in A356 MMCs on their mechanical properties at macro- and nanoscale",
volume = "42",
number = "3",
pages = "115",
doi = "10.1007/s40430-020-2197-6"
}

Vencl, A., Bobić, I., Stanković, M., Hvizdoš, P., Bobić, B. M., Stojanović, B.,& Franek, F.. (2020). Influence of secondary phases in A356 MMCs on their mechanical properties at macro- and nanoscale. in Journal of the Brazilian Society of Mechanical Sciences and Engineering, 42(3), 115.
https://doi.org/10.1007/s40430-020-2197-6

Vencl A, Bobić I, Stanković M, Hvizdoš P, Bobić BM, Stojanović B, Franek F. Influence of secondary phases in A356 MMCs on their mechanical properties at macro- and nanoscale. in Journal of the Brazilian Society of Mechanical Sciences and Engineering. 2020;42(3):115.
doi:10.1007/s40430-020-2197-6 .

Vencl, Aleksandar, Bobić, Ilija, Stanković, Miloš, Hvizdoš, Pavol, Bobić, Biljana M., Stojanović, Blaža, Franek, Friedrich, "Influence of secondary phases in A356 MMCs on their mechanical properties at macro- and nanoscale" in Journal of the Brazilian Society of Mechanical Sciences and Engineering, 42, no. 3 (2020):115,
https://doi.org/10.1007/s40430-020-2197-6 . .

TY  - JOUR
AU  - Veličković, Sandra
AU  - Stojanović, Blaža
AU  - Babić, Miroslav
AU  - Vencl, Aleksandar
AU  - Bobić, Ilija
AU  - Vadaszne Bognar, Gabriella
AU  - Vučetić, Filip
PY  - 2019
UR  - http://link.springer.com/10.1007/s40430-018-1531-8
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8077
AB  - The optimization of wear rate of the nanocomposites with A356 aluminium alloy matrix, reinforced with silicon carbide nanoparticles, was performed through the analysis of the following influences: wt% of the reinforcement, normal load and sliding speed. The nanocomposites were produced by the compocasting process with mechanical alloying preprocessing (ball milling). Three different amounts of SiC nanoparticles, with the same average size of 50 nm, were used as reinforcement, i.e. 0.2, 0.3 and 0.5 wt%. Tribological tests were performed on block-on-disc tribometer (line contact) under lubricated sliding conditions, at two sliding speeds (0.25 and 1 m/s), two normal loads (40 and 100 N) and at sliding distance of 1000 m. Analysis of variance (ANOVA) was applied to determine the influence of different parameters on wear value of tested nanocomposites. It was noticed from ANOVA analysis that normal load, with 33.39%, is the most significant factor affecting the wear rate of nanocomposites. The amount of reinforcement, with 28.90%, also has a significant influence on the wear rate, while the influence of sliding speed, with 23.82%, is smaller. It was found that the prediction of wear rate, by using regression model and Taguchi analysis, were close to the experimental values. © The Brazilian Society of Mechanical Sciences and Engineering 2018.
T2  - Journal of the Brazilian Society of Mechanical Sciences and Engineering
T1  - Parametric optimization of the aluminium nanocomposites wear rate
VL  - 41
IS  - 1
SP  - 19
DO  - 10.1007/s40430-018-1531-8
ER  - 

@article{
author = "Veličković, Sandra and Stojanović, Blaža and Babić, Miroslav and Vencl, Aleksandar and Bobić, Ilija and Vadaszne Bognar, Gabriella and Vučetić, Filip",
year = "2019",
abstract = "The optimization of wear rate of the nanocomposites with A356 aluminium alloy matrix, reinforced with silicon carbide nanoparticles, was performed through the analysis of the following influences: wt% of the reinforcement, normal load and sliding speed. The nanocomposites were produced by the compocasting process with mechanical alloying preprocessing (ball milling). Three different amounts of SiC nanoparticles, with the same average size of 50 nm, were used as reinforcement, i.e. 0.2, 0.3 and 0.5 wt%. Tribological tests were performed on block-on-disc tribometer (line contact) under lubricated sliding conditions, at two sliding speeds (0.25 and 1 m/s), two normal loads (40 and 100 N) and at sliding distance of 1000 m. Analysis of variance (ANOVA) was applied to determine the influence of different parameters on wear value of tested nanocomposites. It was noticed from ANOVA analysis that normal load, with 33.39%, is the most significant factor affecting the wear rate of nanocomposites. The amount of reinforcement, with 28.90%, also has a significant influence on the wear rate, while the influence of sliding speed, with 23.82%, is smaller. It was found that the prediction of wear rate, by using regression model and Taguchi analysis, were close to the experimental values. © The Brazilian Society of Mechanical Sciences and Engineering 2018.",
journal = "Journal of the Brazilian Society of Mechanical Sciences and Engineering",
title = "Parametric optimization of the aluminium nanocomposites wear rate",
volume = "41",
number = "1",
pages = "19",
doi = "10.1007/s40430-018-1531-8"
}

Veličković, S., Stojanović, B., Babić, M., Vencl, A., Bobić, I., Vadaszne Bognar, G.,& Vučetić, F.. (2019). Parametric optimization of the aluminium nanocomposites wear rate. in Journal of the Brazilian Society of Mechanical Sciences and Engineering, 41(1), 19.
https://doi.org/10.1007/s40430-018-1531-8

Veličković S, Stojanović B, Babić M, Vencl A, Bobić I, Vadaszne Bognar G, Vučetić F. Parametric optimization of the aluminium nanocomposites wear rate. in Journal of the Brazilian Society of Mechanical Sciences and Engineering. 2019;41(1):19.
doi:10.1007/s40430-018-1531-8 .

Veličković, Sandra, Stojanović, Blaža, Babić, Miroslav, Vencl, Aleksandar, Bobić, Ilija, Vadaszne Bognar, Gabriella, Vučetić, Filip, "Parametric optimization of the aluminium nanocomposites wear rate" in Journal of the Brazilian Society of Mechanical Sciences and Engineering, 41, no. 1 (2019):19,
https://doi.org/10.1007/s40430-018-1531-8 . .

TY  - JOUR
AU  - Stojanović, Blaža
AU  - Vencl, Aleksandar
AU  - Bobić, Ilija
AU  - Miladinović, Slavica
AU  - Skerlić, Jasmina
PY  - 2018
UR  - http://link.springer.com/10.1007/s40430-018-1237-y
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7710
AB  - This paper presents the investigation of tribological behaviour of aluminium hybrid composites with Al–Si alloy A356 matrix, reinforced with 10 wt% silicon carbide and 0, 1 and 3 wt% graphite (Gr) with the application of Taguchi’s method. Tribological investigations were realized on block-on-disc tribometer under lubricated sliding conditions, at three sliding speeds (0.25, 0.5 and 1 m/s), three normal loads (40, 80 and 120 N) and at sliding distance of 2400 m. Wear rate and coefficient of friction were measured within the research. Analysis of the results was conducted using ANOVA technique, and it showed that the smallest values of wear and friction are observed for hybrid composite containing 3 wt% Gr. The prediction of wear rate and coefficient of friction was performed with the use of artificial neural network (ANN). After training of the ANN, the regression coefficient was obtained and it was equal to 0.98905 for the network with architecture 3-20-30-2.
T2  - Journal of the Brazilian Society of Mechanical Sciences and Engineering
T1  - Experimental optimisation of the tribological behaviour of Al/SiC/Gr hybrid composites based on Taguchi’s method and artificial neural network
VL  - 40
IS  - 6
SP  - 311
DO  - 10.1007/s40430-018-1237-y
ER  - 

@article{
author = "Stojanović, Blaža and Vencl, Aleksandar and Bobić, Ilija and Miladinović, Slavica and Skerlić, Jasmina",
year = "2018",
abstract = "This paper presents the investigation of tribological behaviour of aluminium hybrid composites with Al–Si alloy A356 matrix, reinforced with 10 wt% silicon carbide and 0, 1 and 3 wt% graphite (Gr) with the application of Taguchi’s method. Tribological investigations were realized on block-on-disc tribometer under lubricated sliding conditions, at three sliding speeds (0.25, 0.5 and 1 m/s), three normal loads (40, 80 and 120 N) and at sliding distance of 2400 m. Wear rate and coefficient of friction were measured within the research. Analysis of the results was conducted using ANOVA technique, and it showed that the smallest values of wear and friction are observed for hybrid composite containing 3 wt% Gr. The prediction of wear rate and coefficient of friction was performed with the use of artificial neural network (ANN). After training of the ANN, the regression coefficient was obtained and it was equal to 0.98905 for the network with architecture 3-20-30-2.",
journal = "Journal of the Brazilian Society of Mechanical Sciences and Engineering",
title = "Experimental optimisation of the tribological behaviour of Al/SiC/Gr hybrid composites based on Taguchi’s method and artificial neural network",
volume = "40",
number = "6",
pages = "311",
doi = "10.1007/s40430-018-1237-y"
}

Stojanović, B., Vencl, A., Bobić, I., Miladinović, S.,& Skerlić, J.. (2018). Experimental optimisation of the tribological behaviour of Al/SiC/Gr hybrid composites based on Taguchi’s method and artificial neural network. in Journal of the Brazilian Society of Mechanical Sciences and Engineering, 40(6), 311.
https://doi.org/10.1007/s40430-018-1237-y

Stojanović B, Vencl A, Bobić I, Miladinović S, Skerlić J. Experimental optimisation of the tribological behaviour of Al/SiC/Gr hybrid composites based on Taguchi’s method and artificial neural network. in Journal of the Brazilian Society of Mechanical Sciences and Engineering. 2018;40(6):311.
doi:10.1007/s40430-018-1237-y .

Stojanović, Blaža, Vencl, Aleksandar, Bobić, Ilija, Miladinović, Slavica, Skerlić, Jasmina, "Experimental optimisation of the tribological behaviour of Al/SiC/Gr hybrid composites based on Taguchi’s method and artificial neural network" in Journal of the Brazilian Society of Mechanical Sciences and Engineering, 40, no. 6 (2018):311,
https://doi.org/10.1007/s40430-018-1237-y . .

TY  - JOUR
AU  - Veličković, Sandra
AU  - Stojanović, Blaža
AU  - Babić, Miroslav
AU  - Bobić, Ilija
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1631
AB  - This paper analyses the influence of graphite reinforcement, load and sliding speed with constant sliding distance on tribological behavior of A356 aluminum matrix composites reinforced with 10wt.% silicon carbide and graphite using the Taguchi design. Hybrid composites were produced in the compo-casting process. Tribological tests were performed on a block-on-disc tribometer where the weight percentage of graphite has three variations (0, 3, and 5), as well as load (10 N, 20 N, and 30 N) and sliding speed (0.25m/s, 0.5m/s, and 1m/s), with sliding distance of 300m. The wear of the composite is investigated under dry sliding condition. The specific wear rate was analyzed using Taguchi method with the aim of finding the optimal parameters. By applying analysis of variance, it was determined that the best tribological properties has A356/10SiC/3Gr hybrid composite. It was also found that the greatest impact on specific wear rate has load with the percentage effect of 69.163%, then sliding speed with 14.426% and the interaction between wt.% graphite and load. The dominant wear mechanism is adhesive wear as confirmed by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS).
T2  - Journal of Composite Materials
T1  - Optimization of tribological properties of aluminum hybrid composites using Taguchi design
VL  - 51
IS  - 17
SP  - 2505
EP  - 2515
DO  - 10.1177/0021998316672294
ER  - 

@article{
author = "Veličković, Sandra and Stojanović, Blaža and Babić, Miroslav and Bobić, Ilija",
year = "2017",
abstract = "This paper analyses the influence of graphite reinforcement, load and sliding speed with constant sliding distance on tribological behavior of A356 aluminum matrix composites reinforced with 10wt.% silicon carbide and graphite using the Taguchi design. Hybrid composites were produced in the compo-casting process. Tribological tests were performed on a block-on-disc tribometer where the weight percentage of graphite has three variations (0, 3, and 5), as well as load (10 N, 20 N, and 30 N) and sliding speed (0.25m/s, 0.5m/s, and 1m/s), with sliding distance of 300m. The wear of the composite is investigated under dry sliding condition. The specific wear rate was analyzed using Taguchi method with the aim of finding the optimal parameters. By applying analysis of variance, it was determined that the best tribological properties has A356/10SiC/3Gr hybrid composite. It was also found that the greatest impact on specific wear rate has load with the percentage effect of 69.163%, then sliding speed with 14.426% and the interaction between wt.% graphite and load. The dominant wear mechanism is adhesive wear as confirmed by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS).",
journal = "Journal of Composite Materials",
title = "Optimization of tribological properties of aluminum hybrid composites using Taguchi design",
volume = "51",
number = "17",
pages = "2505-2515",
doi = "10.1177/0021998316672294"
}

Veličković, S., Stojanović, B., Babić, M.,& Bobić, I.. (2017). Optimization of tribological properties of aluminum hybrid composites using Taguchi design. in Journal of Composite Materials, 51(17), 2505-2515.
https://doi.org/10.1177/0021998316672294

Veličković S, Stojanović B, Babić M, Bobić I. Optimization of tribological properties of aluminum hybrid composites using Taguchi design. in Journal of Composite Materials. 2017;51(17):2505-2515.
doi:10.1177/0021998316672294 .

Veličković, Sandra, Stojanović, Blaža, Babić, Miroslav, Bobić, Ilija, "Optimization of tribological properties of aluminum hybrid composites using Taguchi design" in Journal of Composite Materials, 51, no. 17 (2017):2505-2515,
https://doi.org/10.1177/0021998316672294 . .

TY  - JOUR
AU  - Vencl, Aleksandar
AU  - Bobić, Ilija
AU  - Stojanović, Blaža
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5894
AB  - Purpose - Aluminium alloys are frequently applied in automotive and other industries, since they provide mass reduction. Besides positive effects, aluminium alloys have their shortcomings reflected, first of all, in inappropriate tribological properties of these materials. The aim of this research was to enable the production of cheap aluminium alloy matrix composite with favourable combination of structural, mechanical and tribological properties, focusing on the tribological behaviour. Design/methodology/approach - The A356 Al-Si alloy was used as a matrix for producing metal matrix composites in compocasting process. Three different materials, in form of particles, were added to the matrix (Al2O3, SiC and graphite). Hardness and tribological properties (wear, friction and wear mechanism) of heat-treated (T6) samples were examined and compared. Tribological tests were carried out on ball-on-block tribometer under dry sliding conditions. Sliding was linear (reciprocating). Counter body was alumina ball. Average velocity was 0.038 m/s (max. 0.06 m/s), sliding distance was 500 m and normal load was 1 N. Findings - The effect of two different ceramic particles and graphite particles on tribological properties of obtained composites was evaluated. Wear resistance of composites reinforced with SiC particles was higher and coefficient of friction was lower compared to the composite reinforced with Al2O3 particles. A dual hybrid composite (with SiC and graphite particles) showed the lowest value of wear rate and friction coefficient. Dominant wear mechanism for all tested material was adhesion. Research limitations/implications - It seems useful to continue the work on developing hybrid composites containing soft graphite particles with A356 Al-Si alloy as matrix. The major task should be to improve particles distribution (especially with higher graphite content) and to explore tribological behaviour in diverse working conditions. Originality/value - Particulate composites with A356 aluminium alloy as a matrix produced in compocasting process using ceramic particles (Al2O3, SiC) were investigated in many researches, but there are only few detailed analyses of dual composites (with the addition of ceramic and graphite particles). In some previous studies, it was shown that compocasting process, as relatively cheap technology, can obtain good structural and mechanical characteristics of composites. In this study, it was shown that even a low graphite content, under specified conditions, can improve tribological properties.
T2  - Industrial Lubrication and Tribology
T1  - Tribological properties of A356 Al-Si alloy composites under dry sliding conditions
VL  - 66
IS  - 1
SP  - 66
EP  - 74
DO  - 10.1108/ILT-06-2011-0047
ER  - 

@article{
author = "Vencl, Aleksandar and Bobić, Ilija and Stojanović, Blaža",
year = "2014",
abstract = "Purpose - Aluminium alloys are frequently applied in automotive and other industries, since they provide mass reduction. Besides positive effects, aluminium alloys have their shortcomings reflected, first of all, in inappropriate tribological properties of these materials. The aim of this research was to enable the production of cheap aluminium alloy matrix composite with favourable combination of structural, mechanical and tribological properties, focusing on the tribological behaviour. Design/methodology/approach - The A356 Al-Si alloy was used as a matrix for producing metal matrix composites in compocasting process. Three different materials, in form of particles, were added to the matrix (Al2O3, SiC and graphite). Hardness and tribological properties (wear, friction and wear mechanism) of heat-treated (T6) samples were examined and compared. Tribological tests were carried out on ball-on-block tribometer under dry sliding conditions. Sliding was linear (reciprocating). Counter body was alumina ball. Average velocity was 0.038 m/s (max. 0.06 m/s), sliding distance was 500 m and normal load was 1 N. Findings - The effect of two different ceramic particles and graphite particles on tribological properties of obtained composites was evaluated. Wear resistance of composites reinforced with SiC particles was higher and coefficient of friction was lower compared to the composite reinforced with Al2O3 particles. A dual hybrid composite (with SiC and graphite particles) showed the lowest value of wear rate and friction coefficient. Dominant wear mechanism for all tested material was adhesion. Research limitations/implications - It seems useful to continue the work on developing hybrid composites containing soft graphite particles with A356 Al-Si alloy as matrix. The major task should be to improve particles distribution (especially with higher graphite content) and to explore tribological behaviour in diverse working conditions. Originality/value - Particulate composites with A356 aluminium alloy as a matrix produced in compocasting process using ceramic particles (Al2O3, SiC) were investigated in many researches, but there are only few detailed analyses of dual composites (with the addition of ceramic and graphite particles). In some previous studies, it was shown that compocasting process, as relatively cheap technology, can obtain good structural and mechanical characteristics of composites. In this study, it was shown that even a low graphite content, under specified conditions, can improve tribological properties.",
journal = "Industrial Lubrication and Tribology",
title = "Tribological properties of A356 Al-Si alloy composites under dry sliding conditions",
volume = "66",
number = "1",
pages = "66-74",
doi = "10.1108/ILT-06-2011-0047"
}

Vencl, A., Bobić, I.,& Stojanović, B.. (2014). Tribological properties of A356 Al-Si alloy composites under dry sliding conditions. in Industrial Lubrication and Tribology, 66(1), 66-74.
https://doi.org/10.1108/ILT-06-2011-0047

Vencl A, Bobić I, Stojanović B. Tribological properties of A356 Al-Si alloy composites under dry sliding conditions. in Industrial Lubrication and Tribology. 2014;66(1):66-74.
doi:10.1108/ILT-06-2011-0047 .

Vencl, Aleksandar, Bobić, Ilija, Stojanović, Blaža, "Tribological properties of A356 Al-Si alloy composites under dry sliding conditions" in Industrial Lubrication and Tribology, 66, no. 1 (2014):66-74,
https://doi.org/10.1108/ILT-06-2011-0047 . .