2198铝锂合金的熔炼、轧制和热处理

Processing of 2198 Al-Li alloy: melting, rolling and heat treatment

摘要:

铝锂合金具有高比强度和高比模量等优点，广泛应用于航空领域。本文系统研究了2198铝锂合金的制造工艺，成功制备了性能优越的板材，为其工业生产提供了理论依据。采用真空感应熔炼法制备了2198铝锂合金铸锭，均匀化处理后，利用多道次热轧将铸锭轧制为板材，经过固溶、淬火、预变形、自然时效和人工时效处理，板材沿轧制方向的抗拉强度高达486MPa。人工时效过程中析出的T1时效相（Al2CuLi），不仅能明显提高板材强度，而且有利于弱化其各向异性。

关键词:铝锂合金;熔炼;轧制;热处理

Abstract:

Al-Li alloy is widely used in the aerospace field, due to its high specific strength and high specific modulus. The processing of 2198 alloy is investigated. 2198 alloy sheet with excellent mechanical properties is successfully manufactured. It will help the industrial production of 2198 Al-Li alloy. The ingot is melted and cast in vacuum induction melting (VIM) furnace. During the followed homogenization the as-cast microstructure can be completely vanished. The ingot is rolled to sheet with 2mm thickness, via multi-pass hot-rolling. Then, the solution, water quenching, pre-deformation, naturally aging and artificial aging are respectively carried out. The tensile strength of final 2198 Al-Li alloy sheet in the rolling direction is 486MPa. The precipitate T1 generated in the artificial aging can not only increase the strength obviously, but also decrease the anisotropy of 2198 Al-Li alloy sheet.

Key words:Al-Li alloy; melting; rolling; heat treatment