The impact of high-voltage electric discharge treatment of the initial powder mixture on the properties of the composites of the Cu – Al – C and Ti – Al – C systems

DOI: 10.62564/M4-AT2200

Olha Syzonenko, Andrii Torpakov, Mykola Prystash, Yevhen Lypian

Institute of Pulse Processes and Technologies of NAS of Ukraine


The development of new materials by high energy treatment is an important task of modern materials science. Materials consolidated using the spark plasma sintering (SPS) method have 1.5–2 times higher physical and mechanical properties than those obtained by conventional metallurgical methods [1]. High-voltage electric discharge (HVED) preparation of powders allows obtaining a highly dispersed initial powder mixtures, saturated with high-modulus fillers. After consolidation, the materials of the Сu – Al – С system can be used for contacts of electric vehicles, and consolidated composites of the Ti – Al – C system have prospects for use as tool materials. The goal of this work is to study the relationship between the processes of high-voltage electric discharge treatment of the initial powders and the properties of composites of the Сu – Al – С and Ti – Al – C systems. The studies were performed by the variations in the working medium, the type of electrode system, the amplitude of the current, the rate of current growth, and the amount of energy. Dispersity and phase composition were determined for powder mixtures before and after treatment. For consolidated materials, hardness, specific electrical resistance, and wear resistance were studied. After HVED treatment of a powder mixture with an initial composition of 87.5% Al + 12.5% Cu, the average size decreases from 15 μm to 6 μm, while CuAl2 and Al4C3 are formed. For the 85% Ti + 15% Al powder mixture, a decrease in the average size from 20 μm to 6.2 μm was achieved, and up to 20% of TiC is formed. For metal-matrix composites (MMC) of Сu – Al – С system, the hardness reaches 600 MPa, the specific electrical resistance is 0.03 Ω ·mm2/m, the weight loss during wear is 0.12 g per 5 km way. For MMC, consolidated from powders with an initial composition of 85% Ti + 15% Al, the hardness reaches 4 GPa, the specific electrical resistance is 0.02 Ω·mm2/m, the weight loss during wear does not exceed 0.04 g per 5 km of way.

Keywords
high voltage electric discharge, spark plasma sintering, metal matrix composites, hardness, specific electric resistance

Acknowledgments
Work was performed with partial financial support from Research Council of Lithuania and Ministry of Education and Science of Ukraine. Authors would like to express gratitude to the Armed Forces of Ukraine for their bravery.

References
[1] O. Guillon, J. Gonzalez-Julian, B. Dargatz, T.Kessel, G. Schierning, J.Räthel, M. Herrmann, Field-Assisted Sintering Technology/Spark Plasma Sintering: Mechanisms, Materials, and Technology Developments. Adv. Eng. Mater., 2014. Vol. 16. P. 830-849. https://doi.org/10.1002/adem.201300409