Wire arc additive manufacturing of CP-titanium bio-medical alloy

Abstract

Metal additive manufacturing system is a process of fabricating metallic parts by direct fusion in a layer upon layer manner, either using metallic powder or wire as feedstock. Microstructure, mechanical properties, and biocompatibility of WAAM-built samples is investigated. The track deposition is performed to know the optimum process parameters and wall structure is fabricated at these known process parameters. Further, characterization is performed to study the microstructure variations with post processing, such as heat treatment and laser shock peening. The as-built samples exhibited dominance of α phase as revealed from XRD peaks. Heat treatment at 900°C is carried out in vacuum to achieve phase transformation from α→β phase. The increase in fraction of β-phase after heat treatment is confirmed by XRD phase analysis and microscopic images as well. The Laser Shock Peening (LSP) effect is observed up to a depth of 43.4476µm along cross-section. The LSP further improved the surface micro-hardness of heat treated samples. The anti-bacterial biocompatibility test has signified that the LSP treated sample gave better antibacterial effect to the sample surface.