镁合金表面注N及直流磁控溅射Ti-TiN膜研究

在镁合金表面经注N后,通过改变Ar/N2流量比研究直流磁控溅射Ti-TiN膜对镁合金表面耐蚀性和耐磨性影响。利用扫描电镜(SEM)、X射线衍射(XRD)等手段分析镀膜的表面形貌和组织结构,通过显微压痕实验测定镀膜的结合情况,通过动电位极化和摩擦磨损试验研究镀膜的耐蚀性和耐磨性。结果表明:镁合金进行溅射清洗、氮离子注入再进行磁控溅射Ti-TiN膜,可以提高镀膜的结合效果,膜表面产生Ti、TiN晶相,可有效地改善镁合金AZ31的耐磨、耐蚀性能。其中,Ar/N2流量比为11∶2时,获得的注N及直流磁控溅射Ti-TiN膜其耐磨、耐蚀性最好。

Effects of surface roughness of substrate on properties of Ti/TiN/Zr/ZrN multilayer coatings

Ti/TiN/Zr/ZrN multilayer coatings were deposited on Cr_17Ni_2 steel substrates with different surface roughnesses by vacuum cathodic arc deposition method. Microstructure, micro-hardness, adhesion strength and cross-sectional morphology of the obtained multilayer coatings were investigated. The results show that the Vickers hardness of Ti/TiN/Zr/ZrN multilayer coating, with a film thickness of 11.37 μm, is 29.36 GPa. The erosion and salt spray resistance performance of Cr_17Ni_2 steel substrates can be evidently improved by Ti/TiN/Zr/ZrN multilayer coating. The surface roughness of Cr_17Ni_2 steel substrates plays an important role in determining the mechanical and erosion performances of Ti/TiN/Zr/ZrN multilayer coatings. Overall, a low value of the surface roughness of substrates corresponds to an improved performance of erosion and salt spray resistance of multilayer coatings. The optimized performance of Ti/TiN/Zr/ZrN multilayer coatings can be achieved provided that the surface roughness of Cr_17Ni_2 steel substrates is lower than 0.4μm.