Characteristic properties of Al-Cu-SiC_p and Al-Cu-B_4C_p composites produced by hot pressing method under nitrogen atmosphere

摘要

Hot pressing of powders is more effective consolidation method for producing particulate composites than other producing techniques because of improving wettability which gives sound parts without pores. The aim of this study is to produce composites of Al-Cu-SiC_p and Al-Cu-B_4C_p by using hot pressing method and investigating their characteristic properties. The volume fractions of the reinforced (SiC, B_4C) composites were 10, 20 and 30 (vol%). The composites were treated in solution for 24 h at 530 ℃ to evaluate heat treatment effect on the composites then aged in oil bath at 180 ℃ for various ageing periods and hardness reached to a maximum value within 8-10 h using Brinnel hardness (HB) tester. In addition, wear resistance of the aged and unaged composite specimens were also investigated by using a pin-on-disc type apparatus under dry sliding conditions at constant speed using 100, 150 and 220 grade SiC abrasive paper under constant loads of 2, 4, 6, 8 and 10 N at room temperature. As a result, the distribution of the reinforced particle was uniform by examining their microstructures. The hardness and the wear performance of the composite increased with increasing volumetric reinforced particle content. Wear rate increased with 100 grade SiC than 220 SiC grade by additional of the reinforced particulate.