MANUFACTURE OF HIGH TOUGHNESS AND DUCTILITY TI-AL INTERMETALLIC COMPOUND

摘要

PURPOSE: To reduce and control the amt. of Ti₃Al phases in a lamellar structural part and to obtain a high toughness and ductility Ti-Al intermetallic compound by executing secondary heat treatment at a specified temp. to an intermediate body obtd. by subjecting the stock having isometric system Ti-Al phases to primary heat treatment at a specified temp. ;CONSTITUTION: When the transformation point in the case of a mixed structure constituted of Ti₃Al phases a₂ and Ti-Al phases γ is formed by phase transition is defined as T₀, the heat treating temp. T₁ is set to (T₀-50)°C≤T₁≤T₀°C, and the stock having isometric system Ti-Al phases γ' is subjected to primary heat treatment. Then, an intermediate body provided with a lamellar structural part L in which the Ti₃Al phases a₂ and the Ti-Al phases γ are alternately deposited is obtd. Next, the heat treating temp. T₂ is set to 1000≤T₂≤1300°C, and the above intermediate body is subjected to secondary heat treatment. By this method, the volume fractional rate of the Ti₃Al phases a₂ is controlled to 0.05 to 50%, by which the objective high toughness and ductility Ti-Al intermetallic compound Im can be obtd.;COPYRIGHT: (C)1993,JPO&Japio