Forming and Springback Prediction of Strips Under Multi-square Punch Concave Forming Process Considering Partial-unloading Effects

考虑部分卸载效应的多压头凹形成形及回弹预测

To further investigate the forming mechanism and springback characteristics of strips under multi-square punch forming (MSPF) considering partial-unloading effects, a series of concave form ing tests of strips are conducted on the MSPF machine. This paper aims to reveal the physical mecha nism of the elastic-plastic deformation in the MSPF process considering the effect of the forming ap proaches, and derive appropriate mathematical interpretations. The theoretical model is firstly estab lished to analyse the concave forming mechanism and springback characteristics of the strip, and its accuracy is then validated by experimental data. The forming history and load evolutions are depicted to explore the required forming capacity through the proposed analytical method. Besides, the paramet ric studies are carried out to discuss their effects on the springback of the strip. The results suggest that the deformation paths of the strip are influenced by the forming approach, and the springback of the strip in convex forming is larger than that in concave forming.

为了进一步探索考虑部分卸载效应的板条多压头成形机理和回弹特性,本文在船舶数控弯板机上开展一系列板 条凹形成形试验。首先建立板条成形的理论模型,分析板条在凹形成形中的变形机理和回弹特性,并与实验结果对比, 验证该模型的准确性;然后在该理论模型基础上,进一步分析板条的变形历史和加载情况,探索不同加工工况所需的船 舶数控弯板机加工能力;此外还分析成形方式对板条回弹的影响,结果表明,凸形成形的板条回弹量大于凹形成形的回 弹量。