Method of producing titanium aluminide having superior oxidation resistance.

摘要

Ti powders and A l powders are combined to prepare a mixture of 40 SIMILAR 55 at% of A l and the balance of Ti. After CIP and degassing, plastic working by hot extrusion is applied to form a shaped mixture of Ti and A l The shape is then processed by HIP to synthesize titanium aluminide while diffusing A l into the Ti structure to form an A l 2O3 phase occurring from both the reaction between A l and oxygen contained in the Ti structure and the oxides on the A l surface, and to disperse the A l 2O3 to form the A l 2O3 protective film. With the reaction between A l and oxygen contained in the Ti structure and with the "Pegging" effect, both the A l 2O3 phase formed at the grain boundaries of crystals or in the crystal grains of titanium aluminide and the A l 2O3 phase existing on the surface of raw material A l powder peg the surface A l 2O3 film to the surface of the titanium aluminide body. This "Pegging" effect enhances the adhesiveness of the film and improves the oxidation resistance of titanium aluminide. <IMAGE>