Ti3AlC2-Al2O3/TiAl3复合材料在Al液中的熔蚀-磨损行为及其交互作用机制

Corrosion-wear behavior and synergy mechanism of TiAlC-AlO/TiAl composite in molten aluminum

通过对比分析Ti3AlC2-Al2O3/TiAl3复合材料在纯腐蚀、纯磨损及熔蚀-磨损三种条件下的材料流失特征,研究了Ti3AlC2-Al2O3/TiAl3复合材料在Al液中的熔蚀-磨损行为及熔蚀与磨损的交互作用机制。结果表明,Ti3AlC2-Al2O3/TiAl3复合材料在Al液中的熔蚀-磨损体积损失比H13钢的体积损失低了两个数量级,随着载荷和转速的上升,Ti3AlC2-Al2O3/TiAl3复合材料的磨损由磨粒磨损逐渐向黏着磨损转变。Ti3AlC2-Al2O3/TiAl3复合材料的熔蚀、磨损交互作用率的最大值为47.5%,在低载荷或低转速条件下由于铝熔体的润滑作用,Ti3AlC2-Al2O3/TiAl3复合材料甚至表现出负的交互作用。这一方面是由于Ti3AlC2-Al2O3/TiAl3复合材料在Al液中腐蚀时不生成其它界面产物,而仅为极少量Ti元素的溶解;另一方面则是由于TiAl3基体与Al2O3二者所形成的空间网络状结构改善了Ti3AlC2-Al2O3/TiAl3复合材料在Al液中的耐磨损性能。

Through comparing and analyzing the materials loss characteristics under pure corrosion, pure wear and corrosion-wear conditons, the corrosion-wear behavior and synergy mechanism between corrosion and wear of Ti3AlC2-Al2O3/TiAl3 composite in molten aluminum were investigated. The results show that the loss of corrosion-wear of Ti3AlC2-Al2O3/TiAl3 composite is two orders of magnitude lower than that of H13 steel. With the increase of load and speed, the wear of Ti3AlC2-Al2O3/TiAl3 composite changes from abrasive wear to adhesive wear. The synergy ratio of corrosion-wear is less than 47.5% in the experiments. Under the condition of low load or low velocity,the Ti3AlC2-Al2O3/TiAl3 composite even exhibits negative synergy. This is partly due to no intermetallic compound formed in the interface, but just a little Ti dissolved into the molten aluminum when the Ti3AlC2-Al2O3/TiAl3 composite corroded in Al melt. On the other hand, the interpenetrating structure of TiAl3 matrix and Al2O3 reinforcement improves the wear resistance of Ti3AlC2-Al2O3/TiAl3 composite in molten aluminum.