金属板料预应力成形技术研究进展

Research progress on pre-stress forming technology for sheet metal

金属板料成形的主要特征为材料变形过程中的弹性变形比例大、型面定形性较差,并且传统成形工艺对装备的依赖程度高,为提高金属板料工件的成形精度,降低对工艺装备的依赖程度,研究和完善了金属板料成形技术方法和手段。金属板料预应力成形技术是将板料置于弹性变形状态,再施加热、冲击等外载荷,最终实现板料成形。研究结果表明,预应力成形可降低对工艺装备的依赖程度,相比于自由成形,板料的变形趋势可控;随着预应力加载载荷的增大,板料的变形量增大;预应力成形中施加的外载荷形式可采用激光载荷、蠕变时效、喷丸冲击载荷和激光喷丸冲击载荷等形式。

The main characteristics of sheet metal forming are large proportion of elastic deformation in the process of materials deformation,poor formability of profile,and high dependence of the traditional forming process on equipment.Therefore,the technical methods and means of sheet metal forming need to be researched and improved in order to improve the forming precision of sheet metal workpiece and reduce the dependence on process equipment.In the process of pre-stress forming for sheet metal,the sheet is put in the state of elastic deformation,then the external load is applied in the sheet such as thermal load,impact load,and other loads.At last,the sheet deformation is realized.The results show that the pre-stress forming technology reduces dependence on process equipment,and the trend of sheet deformation is controlled relative to unconstrained forming.The sheet deformation amount increases with the increasing of pre-stress load.The external load of pre-stress forming can be laser load,creep aging load,peen impulsive load,laser peening impulsive load,and other loads.