Effects of induced electro-pulsing and aging process on properties and microstructure of 7075 aluminum alloy

• Published in: Materials characterization 2022-10, Vol.192, p.112222, Article 112222
• Main Authors: Xiao, Ang, Huang, Changqing, Wang, Shipeng, Yang, Junqing, Cui, Xiaohui
• Format: Article
• Language: English
• Subjects: 7075 aluminum alloy; Dislocation; Induced electro-pulsing; Second phase
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2022.112222

The effect of induced electro-pulsing of 7075 aluminum alloy in solid solution and pre-deformation was studied. The tensile test results show that material plasticity is recovered and strength is increased by induced electro-pulsing treatment (IEPT). As the discharge time increases, the increase in elongation becomes more obvious. Yield strength, tensile strength, and elongation of once-treated samples increased by 3.7%, 1.3%, and 9.7%, respectively, compared with the untreated sample; Those of twice-treated samples increased by 6.4%, 6.4%, and 27.8%. Microstructure characterization showed that the induced current reduces the dislocation density of the material and promotes advanced precipitation of Guinier-Preston (GP) zones. In addition, the strength of treated samples and untreated samples was almost the same after peak aging treatment, while the elongation increased by 12.15%. High resolution transmission electron microscopy (HRTEM) images show that the size of the η’ phase in the treated alloy is smaller and the alloy exhibits better ductility. •Induced electro-pulsing treatment (IEPT) is used to improve the properties of 7075 aluminum alloy.•After IEPT, the plasticity of the alloy is significantly improved and the strength is slightly increased.•Induced current can promote the advance precipitation of GP region, which results in smaller η' phase after aging.