多道次拉伸和感应电流处理5052铝合金的力学性能和显微组织演变

Mechanical properties and microstructural evolution of 5052 aluminum alloys by multi-pass stretching and induced electro-pulsing treatment

提出一种多道次拉伸和感应电流处理(IEPT)相结合的复合成形方法,采用TEM和EBSD揭示感应电流对材料显微组织和力学性能的影响规律。结果表明,采用4次拉伸5%和拉伸后放电,材料伸长率比原始材料增加145%。预拉伸试样经过IEPT处理后,强度下降、塑性提高,材料的位错密度下降,晶粒变形结构向亚结构转变,同时晶粒尺寸略有增加。感应电流减弱材料的各向异性,出现新的<111>//TD织构。电塑性效应和焦耳热效应的结合增强位错运动和空位移动。采用ANSYS软件模拟板料的温度分布,最高温度达到144.7℃。材料强度的理论计算结果与实验数据一致。

A compound-forming method that combines multi-pass stretching and induced electro-pulsing treatment(IEPT)is proposed.The effects of induced current on the microstructure and mechanical properties of material were investigated using transmission electron microscopy and electron backscatter diffraction measurements.The samples stretched by 5%each time showed 145%increase in elongation after 4 stretching and IEPT cycles.The IEPT caused“stress drop”in pre-deformed sheets,while the plasticity increased.Meanwhile,the dislocation density decreased,the deformation structure changed to the substructure,and the grain size increased slightly.The material anisotropy was reduced and a newá111ñ//TD texture appeared after IEPT.The combination of electrical effect and Joule heating enhanced dislocation mobility and vacancy movement.The temperature distribution,with a maximum temperature reaching 144.7°C,was simulated using ANSYS software.The theoretical calculation results were consistent with experimental data.