Research Of The Effect Of Annealing Process On Microstructure And Properties Of Automobile Al-1.2Mn Alloy

Because of the strong corrosion resistance and good conductivity of Al-Mn alloy,it is widely used as current collector within lithium ion battery.It is of great importance to optimize the production process parameters to obtain excellent final grain structure and comprehensive mechanical properties.Three kinds of annealing processes are designed and compared in this paper.The influence of annealing processes on the microstructure and mechanical properties of the materials and their main reasons are discussed and studied.The following main conclusions have been obtained:(1)After undergone pre-deformation and intermediate annealing process,the sample has obtained excellent organization and performance.After the samples were subjected to a high-temperature intermediate annealing process for a short time,the equiaxed grain structure and more excellent mechanical properties are finally obtained.After the samples were subjected to a low-temperature intermediate annealing process for a long time,the samples obtained fully ultrafine grained structure and multi-scale structure with the increase of annealing temperature.The performance of ultra-fine grain structure is characterized by high strength and poor ductility.The multi-scale structure sample has an excellent combination of strength and ductility due to the effect of back stress strengthening.(2)Compared with various annealing processes,the optimal production process is: 6mm hot rolled sheet in the initial state is annealed at 410 °C for 1h.Then,the material is pre-deformed by 20% cold rolling to 4.8mm.Subsequent low-temperature intermediate annealing at 275 °C for 1 h.After cold rolling to 0.5 mm(92% of total deformation),the rolled samples were annealed at 320 °C for 1 h.