AlCrBN/AlCrSiN纳米晶多层复合涂层的制备及其性能

目的制备高硬度、高耐磨性、自润滑及高热稳定性的AlCrBN/AlCrSiN纳米晶多层复合涂层,探索涂层的微观结构、力学性能、耐磨性能及高温热稳定性能。方法采用多弧离子镀技术在WC-Co硬质合金以及不锈钢基底上,制备AlCrBN/AlCrSiN多层纳米晶复合涂层。采用扫描电子显微镜、X射线衍射、透射电子显微镜、纳米压痕仪等设备,对涂层在不同温度(600~1000℃)下退火前后的表面形貌、微观结构、力学性能、耐磨性能进行系统研究。结果AlCrSiN/AlCrBN涂层为典型的纳米晶复合多层结构,涂层主要由fcc-AlCrN纳米晶镶嵌在非晶的SiNx和BNx中并形成多层结构。涂层具有优异的热稳定性能,其结构能够保持到800℃不发生变化,当温度增加到900℃时,涂层发生调幅分解,形成c-AlN、hcp-AlN和Cr2N等复合结构,在1000℃退火后,涂层结构基本稳定,仍能检测到CrN相。涂层纳米硬度及平均摩擦因数分别为29.15 GPa和0.67。结论AlCrSiN/AlCrBN涂层具有优异的力学性能、耐磨性能及高温热稳定性能,在800℃以下保持稳定,在1000℃退火后仍能保持较高的硬度及良好的耐磨性能,在高速切削刀具中具有良好的应用前景。

Preparation and Performance of AlCrBN/AlCrSiN Nanocrystalline Multilayer Composite Coatings

To extend the service life of cutting tool,AlCrBN/AlCrSiN nanocrystalline multilayer composite coating with high hardness,high wear resistance,self-lubrication and high thermal stability was prepared on the cemented WC-Co carbide and stainless steel substrate by multi-arc ion plating technology.The morphology,structure,mechanical properties and wear resistance of the coating before and after annealing in the range of 600~1000℃were systematically studied by scanning electron microscopy,X-ray diffraction,transmission electron microscopy,nano-indentation and friction and wear tester.The AlCrSiN/AlCrBN coating exhibits a typical nanocrystalline composite multilayer structure with fcc-AlCrN nanocrystals embedded in the amorphous SiNx and BNx.The coating has excellent thermal stability performance,and its structure can be maintained to 800℃without change.When the temperature increases to 900℃,the coating undergoes amplitude modulation decomposition,forming structures such as c-AlN,hcp-AlN and Cr₂N.The structure of coating is stable after annealing at 1000℃,since CrN phase also can be detected in the coating.The coating nanohardness and average friction coefficient are 29.15 GPa and 0.67,respectively.AlCrSiN/AlCrBN coating has excellent mechanical properties,wear resistance and high temperature thermal stability,remains stable below 800℃,and can still maintain high hardness and good wear resistance after annealing at 1000℃,and has good application prospects in the field of high-speed cutting tool coating.