板材零件局部体积成形技术研究

板材局部体积成形技术,或称为板材热冲锻成形技术,为近年来提出的一种板材零件成形方法,其特点是板材冲压成形时不但完成板材零件形状的成形,还兼有局部结构的体积成形,例如局部凸柱、凸台、凸筋等结构的成形,适合于成形镁合金、铝合金等金属的成形,尤其适于替代一些电子器件外壳的铸造加工产品。文章介绍了板材热冲锻成形技术的原理、主要工艺控制参数,并对镁合金盒形件的热冲锻成形过程进行了实验研究和计算机模拟分析。针对带有螺丝柱的典型AZ31B镁合金方盒件,通过实验和有限元模拟,研究了其热冲锻成形工艺。实验表明,在再结晶温度以上冲锻2mm或3mm厚的镁合金板材有很好的成形能力,盒形件的周边和内部凸柱都能同时成形。研究结果表明,合理的模具结构、摩擦润滑条件和加热温度等参数,可以获得侧壁高度均匀、凸柱高度合适、无吸孔和凸柱断裂等缺陷的工件。

Research on local bulk forming of sheet metal parts

The local bulk forming technology of sheet metal parts, also the press forging technology of sheet metal parts, has been proposed and developed in recent years. It has the features that not only the geometries of the workpiece can be formed, local, structures Like concave bosses can also he formed in one process step. It is thus to be possible to replace pressure casting Mg sheet parts in manufacturing of electrical devices. The principle of the process is introduced in the present paper, the main process parameters are discussed. The press forging process of AZ31B Mg sheet parts are discussed on the basis of experiments and computer simulations. It is shown that the Mg sheets can be press formed at temperatures above re-crystalization temperature with good formability. The local structures can be formed in one step. Suitable process conditions including the die structures, the friction conditions and the temperature can lead to forming of box workpieces with uniform side height and local structure heights without process defects.