Studies on mechanical Properties of SiCp / Al - Si Composites
전정식 Jeong Sic Jeon , 고병철 Byung Chul Ko , 유연철 Yeon Chul Yoo , 김경택 Kyoung Taek Kim , 이지환 Chi Hwan Lee
Abstract
Tensile and wear-resistance properties were studied on SiC particle reinforced Al-12Si eutectic alloy(AC8A) composites. The Al-Si alloy was produced by gas atomization process and the composites were fabricated by powder metallurgy route. On hot extrusion process, at an extrusion ratio of 25 : 1 and at 500℃, the Si precipitates and SiC particles were not fractured. During tensile tests the Si precipitates which were Larger than 4㎛ were fractured and the degree of fracture of SiC particles was small. As the Vol.% of SiC increased the fracture sources of the composites were varied from internal cracks of Si precipitates or decohesion of interfaces between SiC and matrix to separation of SiC particles within agglomeration regions. After thermal expousure the width of wear was increased with increasing exposure temperature and time. The wear mode was varied from abrasive wear to delamination wear with increasing SiC volume fraction.