多道次普旋预成形阶段法兰起皱预测

Study on Flange Wrinkling Prediction in Preforming Stage During Multi-Pass Conventional Spinning

多道次普旋包括贴模阶段和预成形阶段,本文主要聚焦于预成形阶段法兰起皱预测.根据普旋预成形阶段变形特征,提出法兰失稳区域内侧为简支条件,外侧为自由边界条件的假设,并推导出符合边界条件用来描述起皱波形的挠度曲面方程.基于能量法建立了法兰起皱预测模型,结合从普旋数值仿真获得的应力场和几何信息,完成了预成形阶段法兰起皱预测.与铝合金半球形构普旋试验对比表明,所建立的预测模型可以准确评估预成形阶段法兰起皱现象.

The multi-pass conventional spinning includes the shaping stage and preforming stage. This paper focuses on the flange wrinkling prediction in the preforming stage. According to the deformation characteristics in the preforming stage, the assumptions that the inner side of the instability region at the flange is a simple support condition and the outside is a free boundary condition are proposed, and the deflection surface equation for describing the wrinkling wave shape that meets the boundary conditions is established. The prediction model of the flange wrinkling is developed based on the energy method. Combining the geometries and the stress fields in the conventional spinning numerical simulation, the flange wrinkling prediction in the preforming stage is realized. Compared with the spinning experiment in an aluminum alloy hemispherical component, the developed model can accurately predict the flange wrinkling in the preforming stage.