Compositional Gradient Films Research Articles

反応性ＤＣスパッタリングによるＴｉ‐６Ａｌ‐４Ｖ合金基板へのＴｉ／Ｏ傾斜皮膜の形成

Coating of Ti-6Al-4V alloy substrates with Ti/O compositional gradient films was carried out by reactive DC sputtering to improve the toughness of the films with respect to mechanical impact, the adhesion of the films, and the biocompatibility of the alloy. Ti/O compositional gradient films were formed by continuously varying the oxygen content of the Ar-O2 sputter gas, and film characteristics were evaluated by SEM image, AES analysis, and hardness measurement. Under visual observation, the deposited films appeared to exhibit good uniformity and adhesion, but under SEM the surface was found to have fine particles dispersed on a smooth accumulated deposit. Under AES, the oxygen concentration in the films decreased gradually from the surface toward the substrate, confirming that Ti/O compositional gradient film had formed. Based on indentation-fracture tests, it was concluded that this method improved both adhesion at the film/substrate interface and film toughness.