Effect of layered polyurethane elastic cushion on quality of surface part in multi-point forming

[摘要] Multi-point forming (MPF) is a dieless forming method. The upper and lower dies of MPF are composed of discrete height-adjustable punches. However, defect will be generated as some particular dimples crease on the smooth surface parts. Therefore, the addition of elastic cushion between the sheet metal and multi-point die is needed to improve the forming quality of surface parts. In this paper, we investigate the forming quality changes of workpiece through dividing polyurethane elastic cushion of the same thickness into different layers. Besides, spherical parts are selected as the study objects. The dynamic explicit algorithm is used to simulate the MPF process and static implicit algorithm is used to simulate springback. The results demonstrate that the values of the strain, stress and residual stress are smaller in process of multi-layers than that of one layer, and the distributions of the stress and strain are more uniform. Based on the results, it was also found that the layered polyurethane elastic cushion can effectively improve the quality of forming parts in MPF.

[发布机构] Dieless Forming Technology Center, Jilin University, No. 5988 Renmin Street, Changchun; 130025, China^1

[效力级别] 生态环境科学

[关键词] Dieless forming;Different layers;Dynamic explicit algorithm;Forming quality;Multi point forming (MPF);Multi-point forming;Static implicit algorithm;Stress and strain