内燃机用Ti600钛合金表面阴极离子镀制备AlCrVN 涂层及其性能研究

Erosion Wear Behavior of Surface Modification AlCrVN Coating on Ti600 Alloy for Internal Combustion Engine

选择阴极电弧离子镀方在内燃机用Ti600钛合金表面制备AlCrVN涂层,并进行组织,力学性能和实验冲蚀磨损性能测试分析。研究结果表明:涂层和基底之间具有均匀的致密组织结构,其厚度约等于4.5μm。AlCrVN涂层内除了含有AlN相以及CrN相以外, AlN相以(101)晶面进行择优生长。涂层内部形成了一些断续的小凹坑,并在小凹坑边缘位置出现一定数量的微裂纹,涂层发生了破裂的现象并生成了一些剥离微片。AlCrVN涂层具有比基体更高的硬度与弹性模量,这使得整体结构能够有效抵抗外部粒子的微切削冲击作用。经过480 s冲蚀之后,AlCrVN涂层形成了5.26μm深度的冲蚀坑。AlCrVN涂层在抗冲蚀磨损能力方面达到了基体材料的近9倍。经过垂直冲击后,试样基体表面形成了大量凹坑,表现出塑性冲蚀特征。

Herein, we experimentally addressed the tribological properties of AlCrVN coatings synthesized by cathodic arc ion plating on Ti600 alloy, an advanced material for internal combustion engine. The microstructures and tribological properties of the AlCrVN coatings were characterized with X-ray diffraction,scanning electron microscopy and by sand-blasting erosion test. The results show that the 4.5 μm thick AlCrVN coatings significantly improved tribological behavior of Ti-alloy.For example, the compact, uniform AlCrVN coating comprised CrN and AlN phases, with <101> preferentially grown AlN grains and some micro-pores surrounded by micro-cracks.In addition to considerably improved hardness/elastic modulus, the erosion resistance, against particle impact of AlCrVN coating, was nearly 8 times greater than that of Ti600 alloy. An eroded pit, 5.26 μm in depth, formed after sand-blasting for 480 s. Vertical sand-blast impact produced high density of eroded pits, indicating a plastic wear mechanism.