润滑条件下短纤维增强镁基复合材料的摩擦磨损行为研究

采用挤压浸渍预制件工艺制备了氧化铝短纤维增强镁基复合材料,并探讨了纤维取向对润滑条件下复合材料摩擦磨损行为的影响.结果表明:挤压浸渍工艺制备的镁基复合材料具有纤维二维择向分布,不同纤维分布对复合材料在润滑条件下的耐磨性能和磨损机制有较大影响.滑动方向垂直于纤维排列方向时,复合材料的磨痕深度小于平行方向,但相对应的钢球的磨损量则高于平行方向.滑动方向垂直于纤维排列方向时复合材料的磨损机制主要包括纤维破碎和基体的磨粒磨损;滑动方向平行于纤维排列方向时复合材料的磨损机制主要表现为纤维剥落和磨粒磨损.

Magnesium Matrix Composites under Lubricated Condition

Magnesium matrix composites reinforced by short fibers were prepared by the squeeze-casting infiltration process, and the effect of fiber distribution on the wear properties were discussed. The fibers in magnesium matrix composites were two-dimensional (2-D) distributed after infiltration process, and the composites in different direction exhibited different tribological property. Composite in parallel direction has a deeper worn track than that in perpendicular direction, but the volumetric wear loss of the counter-part (steel ball) by the composite in parallel direction is lower than that of perpendicular direction. The controlling wear mechanism of the composite in perpendicular direction includes: fracture of fibers and abrasive wear of matrix. The pull out and abrasive wear of matrix are the wear mechanism for the composite in parallel direction.