采用旋转冲蚀磨损试验研究了在7 m·s-1和15 m·s-1冲蚀速度下Al-2.15%Mn合金和Al2O3颗粒增强Al-2.06%Mn合金基复合材料的冲蚀磨损性能, 分析了材料的组织特征及冲蚀磨损后的表面形貌。结果表明: Al-2.15%Mn合金组织由锰在铝中的固溶体及铝锰化合物(MnAl6和Al11Mn4 相)组成; 复合材料的组织在前者基础上, 增加了Al2O3 颗粒; 两种材料在15 m·s-1冲蚀速度下的冲蚀磨损率是7 m·s-1下的20～30倍, 冲蚀速度是影响磨损率的主要因素; 两种材料在磨料加入量为3%时的磨损率均高于1%时的, 且随磨料粒径的增加冲蚀磨损率均先增大后减小; 在3%磨料加入量下, 其冲蚀磨损率极大值均随冲蚀速度的增加向大粒径方向移动; 均匀分布于基体中的Al2O3 颗粒能起到弥散强化的作用, 因此复合材料表现出更优良的抗冲蚀性能。

The erosion-abrasion wear properties of eutectic Al-Mn alloy and its Al2O3 particle reinforced composites were studied at erosion-abrasion rate of 7 m·s-1 and 15 m·s-1 in rotating erosion-abrasion wear test, and the microstructure characteristics and the worn surface of the materials after erosion-abrasion wear test were analyzed. The results show that, the cast Al-Mn alloy was composed of Al-Mn solid solution, MnAl6 and Al11Mn4 phase, while Al2O3 particles appeared in the composite besides the aforementioned microstructure. The wear rate at the erosion-abrasion rate of 15 m·s-1 was 20 to 30 times as large as the wear rate at the erosion-abrasion rate of 7 m·s-1 for two materials. And the major factor of wear rate was erosion-abrasion rate. The wear rates of both materials were higher with 3% abrasive addition than with 1% abrasive addition, and exhibited increase first then decline with increase of abrasive diameter. The maximum wear rate moved toward the abrasive in larger diameter with increase of erosion-abrasion rate when abrasive addition was 1%. The Al2O3 particle reinforced composite exhibited a good erosion-abrasion wear resistance because of dispersion strengthening of Al2O3 particles distributed uniformly in matrix at same erosion-abrasion conditions.