Fabrication and Processing of Gamma Titanium Aluminides - A Review

Abstract

The paper outlines some research work that has been conducted in Harbin Institute of Technology, on the fabrication of TiAl alloys. The review is presented with special emphasis on some different manufacturing routes of TiAl alloys, including investment casting, canned forging and sheet rolling, mechanical milling and rapid solidification. Investment casting has been developed to manufacture near-net shape TiAl blades. Also included are current development of canned forging and rolling for TiAl sheets. Then, TiAl nanocrystalline powders gained through low temperature and two steps mechanical milling were researched. And considerably refined TiAl alloys with Y additions were produced by rapid solidification and the microstructure evolution with Y addition was studied. Details of the processing route and microstructure related to different processing method will be presented.