制备工艺对电池壳用Al-Mn系合金成形性微观机制的影响

Influence of preparation process on micro-mechanism of formability for Al-Mn alloy of battery shell

采用金相显微镜、共聚焦显微镜、扫描电子显微镜、透射电镜、电子背散射衍射技术和力学分析等手段研究了Al-Mn系合金板材的制备工艺对锂离子电池壳用板材成形性微观机制的影响。结果表明:与热轧供坯制备的板材相比,由于铸轧供坯生产的板材的表面粗糙度及氧化膜厚度偏大,导致冲压时碎屑卡模而影响了电池壳的成形效率。通过铸轧供坯在580℃的均匀化退火细化晶粒和分散铸轧枝晶间隙的第二相组织,以及在380℃成品退火控制第二相尺寸及其弥散析出,使轧制织构减弱,随机织构和Cube织构增强,控制一定的力学性能使各向异性减弱,制耳率降低,进而使板材的成形性提高。

The influence of preparation process of Al-Mn alloy plates on the micro-mechanism of formability for lithium ion battery shell plates was studied by means of metalloscope,confocal microscope,scanning electron microscope,transmission electron microscope,electron back scattering diffraction technology and mechanical analysis.The results show that compared with the plates prepared by hot-rolling billet,the surface roughness and oxide film thickness of the plates produced by casting-rolling billet are larger,which causes debris to get stuck during stamping and affects the forming efficiency of battery shell.Through the homogenization annealing of the casting-rolling billet at 580,the grains are refined and the second phase structure of casting-rolling dendrite gap is dispersed.And through the finished product annealing at 380℃,the second phase size and the dispersion precipitation is controlled to weaken the rolling texture and strengthen the random texture and Cube texture.By controlling a certain mechanical properties,the anisotropy is weakened and the ear-making rate is reduced,thus the formability of the plate is improved.