LASER POLISHING OF ADDITIVELY MANUFACTURED TITANIUM ALLOY IN OPEN AIR ATMOSPHERE

Abstract

Additive manufacturing, which has gained significant growth in recent years, enables the manufacturing of complex geometries. However, additively manufactured parts often need post-processing to improve the surface quality and mitigate residual stresses. Laser polishing of metals is a high-quality technology to reduce the surface roughness of the metals. In this work, the surface morphology and microstructure of Ti-6Al-4V (Ti64) Grade 5 are investigated before and after the laser polishing process. The distinctness of this study is that the specimen was polished in a completely open atmosphere without any protective gas. The results revealed that the surface roughness was able to improve up to 50% even in a complete open-air atmosphere. A recast layer with a high degree of oxidation was obtained during the polishing of titanium alloy due to Oxygen in the atmosphere. According to the amount of oxidation level, the polished surface of the material was hardened.