Mechanical properties and microstructural evolution of 5052 aluminum alloys by multi-pass stretching and induced electro-pulsing treatment
(1. Light Alloy Research Institute, Central South University, Changsha 410083, China;
2. College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China;
3. State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China)
2. College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China;
3. State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China)
Abstract: 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 new á111？//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.
Key words: 5052 aluminium alloy; induced electro-pulsing; texture evolution; Joule thermal simulation; strength calculation