Laser Surface Modification of Ti-6Al-4V with Addition of Pr

摘要

The behaviour of oxidation at elevated tem-peratures and fretting in the laser-alloyed layer ofTi-6Al-4V with the addition of Pr was studied.The results show that the addition of Pr changes thestructure of oxide scale of Ti-6Al-4V,controls theshort-range diffusion of oxygen to thescale/substrate interface and increases the adhe-sion and ductility of the scale,thus changing theoxidation kinetics and considerably reducingoxidation rate.The analysis of fretting test showsthat the existence of high hardness layer in the al-loyed zone,fine dendrites perpendicular to the sur-face of the high hardness layer and the oxide scaleproduced during fretting at elevated temperaturesare all beneficial to the improvement of wear resist-ance.