Experimental study on Ti alloy plate fabrication by vacuum selective laser melting

Abstract

We demonstrated that a Ti-6Al-4V plate, which is clinically used for artificial bone and hard tissue implant in human body because of their light and biocompatibility, were fabricated by SLM process in vacuum. The chamber’s pressure was set to 1.0×10-3 Pa to prevent the Ti64 powder from oxidizing. The base plate of the powder bed was vertically dropped in determined steps, and Ti64 powder supplied from the powder feeder was then smoothed by a roller on top of the powder bed. The single-mode fiber laser irradiated and melted the powder bed to make a molten pool in order to form 2D metallic structures In order to investigate the laser melting and solidification dynamics, a process of Ti 64 plate fabrication was captured by high speed video camera. It was also determined that crystal orientation was evaluated with X-ray diffraction (XRD) and energy dispersive X-ray (EDX) spectroscopy From EDX analysis, the chemical compounds were not changed from powder to fabricated sample. And it was recorded from the powder peaks of α (1011), α (0002), α (1010), and α (1012) that the crystal orientation is composed mainly of martensitic alpha by XRD analysis. Diffraction peaks corresponding to β (110) were detected in vacuum SLM processed samples.