基体偏压对CrAlN涂层海水环境摩擦学性能的影响

Effects of Substrate Bias on Tribological Performance of CrAlN Coating in Seawater

本文采用多弧离子镀技术用5种不同偏压在316L不锈钢上沉积CrAlN涂层。使用X射线衍射(XRD)和扫描型电子显微镜(SEM)表征涂层的结构,并使用纳米压痕测试各涂层的硬度。用球-盘往复式摩擦磨损试验机对涂层在海水环境中的摩擦磨损性能进行测试。结果表明,随着偏压增大,CrAlN涂层表面大颗粒减少,而晶向生长特征也减弱。其结构在80V偏压下较为致密,但100V偏压下显示出典型的柱状晶结构特征。随着偏压增大,硬度也随之提高。各涂层在海水中摩擦系数相差不大,摩擦系数都先增大然后不断降低,最终达到相对平稳。在40V、60V和80V偏压下涂层在海水中的磨损率相对较小,且80V偏压下CrAlN涂层磨损率最低。在100V偏压下CrAlN涂层磨痕表面出现了剥落坑,EDS扫描结果显示该处涂层已完全剥落。

The CrA1N coatings were deposited on 316L stainless steel by arc ion plating on five different substrate biases. The coating structure was characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. Hardness was tested by nanoindentation. The friction and wear properties of coatings were investigated by ball-on-disk tribometer in artificial seawater. The results showed that the number of macroparticle and grain size decreased with the increase of bias. The coating structure under the bias of 80V was dense while that under 100V presented typical columnar crystals. The hardness for the coatings increased with the increase of bias. The friction coefficients of the coatings were close to each other. The coefficients increased first and then decreased gradually, finally reaching the steady values. The wear rates of the coatings under the biases of 40V, 60V and 80V were relatively lower. The wear rate under 80V was the lowest. The flake pits wear was observed in the wear track of the coating under 100V and the EDS results confirmed that the coatings were worn out.