IN-SITU ALLOYING PROCESS OF TI6AL4V-xCU STRUCTURES BY DIRECT METAL LASER SINTERING

Abstract

In this paper the fabrication of in-situ Ti6Al4V-xCu alloy structures by DMLS are investigated. Ti6Al4V is a commonly used biomedical alloy because of it suitable mechanical and biocompatible properties. Copper is a proven anti-bacterial agent and in small amounts is not toxic to the human body. Ti6Al4V-xCu implants can be constructed to have a biocompatible structure with copper additions to reduce the risk of bacterial infection and implant failure. Infection at the bone–implant interface is the most probable reason for implant failure directly after implantation. Ti6Al4V powder was mixed with Cu powder to form a master alloy. Optimal process parameters need to be established for in-situ alloying of Ti6Al4V-xCu to form dense parts with suitable surface quality. The effect of laser scanning speeds and hatch distance on surface characteristics was investigated. The surface roughness, chemical composition and distribution of Cu near the surface and within the synthesized layer, as well as micro hardness were considered. A rescanning strategy was employed and showed improved alloy homogeneity and surface quality.