Role of Al2O3 fiber in eutectic Al-Si alloy composites
(1. School of Materials Science and Engineering,
Xi′an University of Technology, Xi′an 710048, China;
2. Laboratory of Materials Science in Space,
Northwestern Polytechnical University, Xi′an 710072, China;
3. Department of Mechanical Engineering, Fukui University,
Fukui 910-8507, Japan)
Xi′an University of Technology, Xi′an 710048, China;
2. Laboratory of Materials Science in Space,
Northwestern Polytechnical University, Xi′an 710072, China;
3. Department of Mechanical Engineering, Fukui University,
Fukui 910-8507, Japan)
Abstract: The effects of Al2O3 fiber on wear characteristics of eutectic Al-Si alloy composites were studied using a pin-on-disk tester under dry sliding condition. The results show that the Al2O3 fiber can make matrix grain be fine, specially the eutectic Si be finer and prevent the plastic flow of matrix and prohibit the crack propagation in the wear layer, thereby it can remarkably improve the mechanical property and the wear resistance of the MMCs. Since (Al2O3) fiber plays a role of certain framework in protecting the matrix against crash, it can eliminate the severe wear of MMCs with higher φf of fiber from the beginning of test. At mild stage, when φf is in the range of 8%~10%, the wear rates are the lowest. With increasing φf of Al2O3 fiber, the wear mechanism of MMCs can be transformed from adhesive delamination to brittle breakaway.
Key words: Al2O3 fiber; eutectic Al-Si alloy; composite; wear mechanism