Process of Double Glow Surface Plasma Niobizing of Ti-6Al-4V Alloy
The double glow surface plasma niobizing was performed on Ti-6Al-4V alloy. The effects of alloying temperature and time on element content and thickness of the alloyed layer were studied. The optimum processing parameter was determined. The microstructure, chemical composition and thickness of the alloyed layer were observed by OM and glow discharge spectrum. The results show that the thickness and composition of the alloyed layer are related to the alloying temperature and time on the condition of a constant pressure and fixed cathode. A deposit layer on the surface of Ti-6Al-4V is formed by too long alloying time or too high temperature. The appropriate thickness and composition distribution of the alloyed layer made by an optimized process parameter of 850℃ × 3 h is useful to overcome the poor wear resistances of Ti-6Al-4V alloy.