TC4钛合金表面电弧离子镀TiN/CrN纳米多层薄膜研究

用电弧离子镀技术在TC4钛合金基体上通过改变偏压制备了4组TiN/CrN薄膜,对薄膜的表面形貌、厚度、相结构、硬度、膜基结合力和摩擦系数等组织、性能进行了测试表征。结果表明,薄膜是由TiN相和CrN交替叠加构成的纳米多层薄膜,薄膜的调制周期为60 nm,总的厚度约为480 nm。与基体钛合金相比,镀膜后样品的表面性能与偏压幅值密切相关并有显著提高:显微硬度从基体的3 GPa提高到16.5~24.7 GPa;摩擦系数从基体的0.35大幅度降低到0.14~0.17;薄膜与基体结合牢固,膜基临界载荷在60~80N之间。经电弧离子镀TiN/CrN纳米多层薄膜处理后,TC4钛合金可以满足沙粒和尘埃磨损条件下的耐磨性能要求。

Growth and Mechanical Properties of TiN/CrN Multilayers by Arc Ion Plating on TC4 Ti Alloy

Four different types of nano-multi-layered TiN/CrN films were deposited by arc ion plating on TC4 alloy substrates.The impacts of the deposition conditions,including the substrate species,pulsed bias voltage,and periodicity of the multi-layers,were evaluated.The microstructures and mechanical properties of the multi-layers were characterized with X-ray diffraction,X-ray photoelectron spectroscopy,scanning electron microscopy,and conventional surface probes.The results show that the 480 nm thick multi-layers consist of the TiN and CrN layers with a periodicity of 60 nm,and that the pulsed bias voltage strongly improves the surface properties.When it comes to the mechanical properties,the coating on TC4 alloy substrate outperforms that on the Ti substrate.For instance,the microhardness increased from 0.3 GPa(on the Ti substrate) to 16.5~24.7 GPa;its friction coefficient dropped from 0.35 to 0.147~0.17;its wear-resistance also increased.Moreover,the interfacial adhesion was found to be 60~80 N.