强塑性变形下Al-Cu合金不同析出相的回溶及性能变化

Re-dissolution and Evolution of Properties of Different Precipitated Phases in Al-Cu Alloy under Severe Plastic Deformation

采用双向反复压缩变形研究了Al-Cu合金中不同析出相的回溶速度及性能变化。结果表明:在强塑性变形过程中,GP区回溶的速度最快,介稳相(θ″+θ′及θ′)次之,稳定相(θ)最慢。强塑性变形引起的脱溶作用较小,而导致第二相回溶的作用较大。GP区状态下合金在压缩后硬度升高最大,过饱和固溶体、介稳相(θ″+θ′)和稳定相(θ)状态下依次减小。

The speed of re-dissolution and changes of properties of different precipitated phases in Al-Cu alloy are studied using double-directional alternative compress deformation. It is obtained that the speed of re-dissolution of GP zone is the fastest , that of metastable phase（θ″-θ′and θ′） is second , and that of equilibrium phase （θ）is the slowest during severe plastic deformation. The precipitated.effect induced by severe plastic deformation is smaller, and the re-dissolved effect led by it is larger. The increases of hardness of alloys at GP zone state is maximum after compress deformation, and those in metastable phase（θ″＋θ′） state, supersatured solid solution state, metastable phase （θ′）state , and equilibrium phase （θ） state gradually diminish.