多弧离子镀制备CrAlSiN/TiAlSiN纳米涂层的结构和性能研究

目的研究调制周期对CrAlSiN/TiAlSiN纳米复合涂层结构和力学性能的影响。方法采用多弧离子镀技术,以AlCrSi靶和AlTiSi靶作阴极弧靶材料,通过改变衬底的转速(转速分别为2、4、6、8r/min)来调整涂层结构的周期,制备不同调制周期CrAlSiN/TiAlSiN纳米复合涂层。用X射线衍射仪、X射线光电子能谱仪、扫描电子显微镜和原子力显微镜,测量了涂层的组织结构、化学成分、表面及截面形貌,用显微硬度计、划痕试验仪和摩擦仪测量了不同调制周期的涂层的力学性能。结果不同转速下,CrAlSiN/TiAlSiN纳米复合涂层具有相同的晶相结构,包含CrAl、CrN和TiN,其中Al元素几乎全部固溶在CrAl相中。Si元素在涂层中以非晶相的形式存在或被非晶化合物所包裹。随着转速的增大,复合涂层的硬度呈现先增大后减小的趋势,而摩擦因数与均方根粗糙度则呈现出先减小后增大的趋势,即硬度越大,摩擦因数和均方根粗糙度越小。结论CrAlSiN/TiAlSiN纳米复合涂层的硬度和摩擦因数受调制周期的影响较大。当转速为6r/min时,制备的涂层具有最大的显微硬度(38GPa)和最小的摩擦因数(0.375)。

Structure and Properties of CrAlSiN/TiAlSiN Nano-coatings Prepared by Multi-arc Plasma Deposition

The work aims to study effects of modulation period on structure and mechanical properties of CrAlSiN/TiAlSiN nanocomposite coatings. Periods of coating structure was adjusted by changing revolving speed of substrate (revolving speed as 2, 4, 6 and 8 r/min). Nanocomposite coatings with different modulation periods were prepared by cathodic multi-arc ion plating with CrAlSi and TiAlSi as the cathode arc target materials. Microstructure, chemical composition, surface morphology and cross-sectional morphology of the coatings were measured with X-ray diffractometer, X-ray photoelectron spectrometer, scanning electron microscopy and atomic force microscopy, respectively. Mechanical properties of the coatings with different modulation periods were analyzed with microhardness tester, scratch tester and friction tester. The CrAlSiN/TiAlSiN nanocomposite coatings had the same phase structure at different revolving speed, including CrAl, CrN and TiN phases. Al element was nearly subject to solid solution in CrAl phase. Si element was present in the coating as an amorphous phase or was wrapped with an amorphous compound. With the decrease of the revolving speed, hardness of the composite coatings first increased and then decreased while friction coefficient and RMS roughness first decreased and then increased. The higher the hardness was, the lower the friction coefficient and RMS roughness would be. The hardness and friction coefficient of the CrAlSiN/TiAlSiN nanocomposite coatings are significantly affected by the modulation periods. At the revolving speed of 6 r/min, the coatings have a maximum microhardness of 38 GPa and lowest coefficient of friction (0.375).