采用扩散共渗的方法在TC4合金表面制备了Zr增效硅化物涂层,研究了涂层在600℃时的摩擦磨损性能,讨论了其磨损机制.结果表明:所制备的涂层具有多层结构,由(Ti,X)Si2(X代表Zr,Al和V)外层,TiSi中间层和Ti5Si4+Ti5Si3内层组成;渗剂中添加Zr能够抑制涂层的生长速率,有利于降低涂层的内应力,改善其组织致密性.涂层的硬度明显高于TC4合金,且由外向内呈梯度降低趋势.高温摩擦磨损试验结果表明,Zr增效硅化物涂层能够为TC4合金提供良好的高温磨损防护;与GCr15对磨时,涂层的表面只发生了轻微的磨损,主要为GCr15在其磨损面的擦涂和一定程度的氧化磨损;与Al2O3球对磨时,磨损机制为犁削磨损、疲劳磨损、黏着磨损和氧化磨损.%Zr modified silicide coatings were prepared on TC4 alloy by Si-Zr co-deposition, the wear behavior of the coatings were investigated at 600℃, and the wear mechanisms were discussed. The results show that the obt-ained coating has a multi-layer structure, consisting of a (Ti, X)Si2(X represents Zr, Al and V elements) outer layer, a TiSi middle layer and an inner layer composed of a mixture of Ti5Si4+Ti5Si3. Addition of Zr in the pack mixtures can reduce the residual stress in the coating by lowering the coating growth rate, leading to a more compact coating structure. The micro-hardness of the coating is obviously higher than that of TC4 alloy, which shows a decrease tendency from the coating surface to its substrate. The high temperature wear tests reveal that the Zr modified silicide coating can offer effective protection for TC4 alloy at high temperatures. When using GCr15 ball as the counterpart, very slight wear occurred on the worn surface of the coating, and the main wear manners should be the transfers of GCr15 to the coating surface besides a certain extent of oxidation wear. Sliding against Al2O3ball, the main wear mechanisms of the coating are considered to be plough wear, fatigue wear, adhesive wear, and oxidation wear.
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