Cu-Cr-In合金形变热处理过程的组织与性能演变研究

Microstructural Evolution and Mechanical Property of Cu-Cr-In Alloy during Thermo-Mechanical Treatment

对Cu-0.70Cr-0.15In合金在形变热处理过程中的显微组织及电导率、抗拉强度等演变规律进行了研究。合金铸态组织中,在α相周围不连续分布着(α+Cr)共晶体,In均匀分布于α基体相中;合金在低于500℃时效,依然能清晰保持着时效前冷变形组织形貌,550℃时效120 min后可观察到少量的再结晶组织。结果表明,在经过1000℃×60 min的固溶处理及应变ε为80%的冷变形工艺后,合金在450℃×60min时效后具有最优的电导率和抗拉强度综合性能,其电导率和抗拉强度分别达到81.41%IACS和544 MPa,延伸率δ为13%。合金时效后再经过45%的冷变形,其抗拉强度得到迅速提升,达到641 MPa,电导率和延伸率分别仍可维持在81.2%IACS和4.5%。软化温度测试结果表明,合金时效态和"时效+冷变形"态的软化温度分别为525和440℃。

Microstructures of Cr-0.70Cr-0. 15In alloy during the thermo-mechanical process were observed and the electrical conduc- tivity and tensile strength were tested. The α matrix phase was surrounded by （α ＋ Cr） enteetic discontinuously while indium（In） dissolved in the α matrix phase homogeneously. Typical microstructures after cold deformation were preserved after ageing at temperatures below 500 ℃ , while a small amount of recrystallization structures were observed after aging at 550℃ for 60 min. The results showed that the alloy aged at 450 ℃× 60 min had a good combination of properties-electrical conductivity, tensile strength and elongation being 81.41% IACS, 544 MPa and 13% , respectively. The tensile strength increased to 641 MPa after 45% cold deformation following aging, and conductivity and elongation were still maintained at 81.2% IACS and 4.5%. The softening tests showed that softening temperature of the as-aged and ageing-cold deformation states reached 525 and 440 ℃ , respectively.