Preparing method for large-size beta-gamma TiAl alloy plate

Abstract

The invention discloses a preparing method for a large-size beta-gamma TiAl alloy plate and relates to a preparing method for the TiAl alloy plate. According to the purpose, the problems that due to the fact that a TiAl alloy hot working window is narrow, the plate is likely to be cracked and is hardly formed in the large-size TiAl alloy plate preparing process due to cooling in the non-isothermal rolling process, and secondary cracking of the plate is caused in the machining sheath removing process are solved. The method includes the steps that firstly, a TiAl alloy blank is prepared; secondly, a sheath is machined; thirdly, a glass lubricating agent is sprayed; fourthly, the TiAl alloy blank is subjected to sealing; fifthly; a high-temperature rolling stage is conducted; sixthly, residual stress is removed through homogenizing heat treatment; and seventhly, the sheath is removed through machining, and the large-size beta-gamma TiAl alloy plate is obtained. The preparing method is suitable for preparing of the large-size beta-gamma TiAl alloy plate.

Description

Technical field [0001] The invention relates to a method for preparing TiAl alloy plates. Background technique [0002] TiAl alloy has good physical and mechanical properties, and the density is less than half of that of Ni-based alloy (3.9~4.2g / cm 3 ), is considered a high-temperature structural material with great development potential. After years of research, the development of TiAl alloy has entered the practical stage. At present, TiAl alloy missile tails, automobile exhaust valves and engine turbine blades prepared by casting, forging and superplastic forming methods have been widely used in aerospace vehicles and automobile engines. And other fields. However, with the rapid development of aviation and aerospace technology, in order to further improve the overall performance of the aircraft, higher requirements have been put forward for the overall weight reduction and endurance of the aircraft. The development of traditional high-temperature Ti alloys has reached the lim...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problems that the plate is easy to crack and difficult to form due to the narrow thermal processing window of the TiAl alloy and the temperature drop in the non-isothermal rolling process during the preparation of the large-size TiAl alloy plate, and the process of removing the sheath during mechanical processing To solve the problem of secondary fracture of the plate, a method for preparing a large-size beta-gamma TiAl alloy plate is provided