Evaluation of tribological properties of nano-multilayered thin hard coatings by a slurry jet impact test and its application

为了快速评价薄、单层或多层硬质涂层的摩擦学性能，提出了一种新型的固体颗粒冲击试验--浆体射流试验。(1)通过浆料射流高速垂直冲击TiN、CrN、TiCN等PVD涂层，发现涂层的耐磨性远高于基体材料，当涂层被穿透时，基体材料的磨损率显著增加。(2)通过使用泥浆射流冲击试验，可以对PVD涂层钻头的磨损性能进行快速且高度可重复的评估。(3)沉积在钻头上的PVD涂层显示出与用作参考样品的板试样上的涂层相同的耐磨性。(4)对于本研究中包括的涂层，TiN被证明具有最高的耐磨性，而CrN是最差的。(5)CrNi涂层的耐磨性随Ni含量的增加而降低。(6)CrN（CrNi）涂层的耐磨性排序与其显微硬度有很好的相关性，表明该评价方法快速、简便。因此，在评估涂层和涂层工具时，它可以优先用作筛选测试。

We proposed slurry jet, a new type of solid particle impact test, in order to quickly evaluate tribological properties of thin, single layered or multilayered hard coatings.(1) By slurry jet 1 μm alumina particles were impacted at high velocity perpendicular to thin PVD coatings of TiN, CrN, TiCN, the coatings proved to have much higher wear resistance than the substrate material, and, consequently, the wear rate increased significantly to the higher level of the substrate material when the coatings were penetrated.(2) By using a slurry jet impact test, fast and highly reproducible evaluation of wear properties of PVD coated drills can be made.(3) The PVD coatings deposited on the drills showed the same wear resistance as those on the plate specimens used as reference samples.(4) For the coatings included in this study, the TiN proved to have the highest wear resistance, whereas the CrN was the worst.(5) The wear resistance of CrNi coatings decrease with increasing the concentration of Ni.(6) The ranking of wear resistance for CrN (CrNi) coatings show good correlation to their micro hardness.We conclude that the proposed evaluation test is fast and easy to accomplish. Thus, it can preferentially be used as a screening test when evaluating coatings and coated tools.