High temperature mechanical properties of TiAl intermetallic alloy parts fabricated by metal injection molding

Abstract

It is not easy to fabricate the complicate shaped titanium aluminide (Ti-Al) components by conventional methods such as machining or forging, and casting leads to inhomogeneous microstructures. Metal injection molding (MIM) has the potential to be a cost-efficient process and near net shape technique, especially for the complex shaped mass-produced components. In this study, Ti-Al intermetallic alloy compacts were fabricated through MIM technique. Sound compacts with over 95 % of relative density and without any warpage or defects were obtained thorough MIM process. Different microstructures of duplex, near lamellar, and full lamellar were obtained by changing the sintering temperature. Their tensile strength at room and high temperature is 85 to 90 % of that of wrought material. Tensile strength of MIM compact would be expected the same level with cast materials by optimization of sintering conditions, densification by HIP treatment and so on.