基体偏压模式对CrN薄膜结构和阻氢性能的影响

Effect of Substrate Bias Mode on Structure and Hydrogen Resistance of CrN Thin Films

为了避免金属材料因为氢扩散而导致的失效,通常在其表面制备氧化物或氮化物等的阻氢薄膜,而薄膜的微观组织、晶体结构等对其阻氢性能的影响显著。本文在不锈钢基体上制备出CrN阻氢薄膜,系统研究了高/低基体偏压调制模式对CrN薄膜结构和阻氢等性能的影响。采用高功率磁控溅射技术在四组基体偏压模式下分别制备了具备一定高温抗氧化性的CrN阻氢薄膜。结果表明:20min×3模式下薄膜为双层结构,其余均为单层薄膜;基体偏压为100V和500V时,膜层受离子的轰击效果差别很大;10min×6模式下因为频繁地变换基体偏压,柱状晶来不及生长就被打碎,膜层最薄,但晶粒细化,膜层致密度最高;20min×3模式下,薄膜的氢抑制率最高,达到95.7%,氢原子的扩散系数最小,相比于316L不锈钢基体降低了3个数量级;四种基体偏压模式下,CrN薄膜的高温抗氧化性能区别不大,其单位面积氧增重均约为316L不锈钢基体的一半,即实验制备的CrN薄膜抗氧化性能比316L不锈钢基体提高1倍,其均具备优异的高温抗氧化性能。

In order to avoid the failure of metal materials due to hydrogen diffusion,oxide or nitride films are usually prepared on the surface of metal materials.The microstructure and crystal structure of the films have significant influence on the hydrogen resistance.In this paper,CrN hydrogen barrier films were prepared on stainless steel.The effects of high/low substrate bias modulation mode on the structure and hydrogen resistance of Cr N films were studied systematically.CrN thin films with high temperature oxidation resistance were prepared by high power pulsed magnetron sputtering under four groups of substrate bias modes.The results show that under 20 min×3 mode,the films are double-layer structure,and the others are single-layer films.When the substrate bias is 100 V and 500 V,the impact effect on the film is very different by ion.Under 10 min×6 mode,the columnar crystal is broken before it grows because of frequent matrix bias change,so the film is the thinnest,but the grain is refined and the density of the film is the highest.Under 20 min×3 mode,the hydrogen inhibition rate of the film was the highest,reaching 95.7%,the diffusion coefficient of hydrogen atom is the smallest,which is 3 orders of magnitude lower than that of316 L stainless steel.The oxidation resistance of CrN films is not much different under the four kinds of substrate bias modes,and the oxygen gain per unit area is about half of that of the 316 L stainless steel.The oxidation resistance of CrN films prepared by this experiments is twice that of the 316 L stainless steel,and they have excellent high temperature oxidation resistance.