拉/压冷变形对2A14铝合金时效强化的影响

利用X射线衍射仪和DSC差热扫描量热仪进行测试,结合铝合金的析出相强化和位错强化理论模型,研究了在固溶-拉/压冷变形-时效过程中2A14铝合金强度的变化规律。结果表明:相比于压缩冷变形,拉伸冷变形引入的位错密度较大,因而位错强化作用更强;拉伸冷变形欠时效阶段(θ相析出之前)促进合金中强化相θ′相的析出,过时效阶段(θ相析出之后)抑制θ相的析出,拉伸冷变形的析出强化效果更好。经过拉伸冷变形的2A14铝合金时效强化效果更加显著。

Effect of tensile/compressive cold deformation on strengthening of 2 A14 aluminum alloy after aging

Strength of solution treated 2A14 aluminum alloy during aging process under tensile or compressive cold deformation conditions was studied by using X-ray diffractometer and DSC differential scanning calorimetry with the help of precipitation phase strengthening and dislocation strengthening theoretical model of aluminum alloy.The results show that compared with compressive cold deformation,the dislocation density introduced by tensile cold deformation is greater,so the dislocation strengthening effect is stronger;In the under-aging stage(beforeθphase precipitates)of tensile cold deformation,the precipitation of the strengthening phaseθ’phase in the alloy is promoted.In the over-aging stage(afterθphase precipitates),the precipitation of theθphase is suppressed,and the precipitation strengthening effect of tensile cold deformation is better.The strengthening effect of the 2A14 aluminum alloy after tensile cold deformation is more significant.