大型厚壁椭圆封头多次热冲压成形分析

Analysis of multi-hot stamping forming for large thick-wall ellipse head

采用有限元法对大型厚壁椭圆封头的一次和多次热冲压成形工艺进行数值模拟。对比分析厚壁封头在两种成形工艺下的压机成形载荷和封头成形壁厚的差异,并研究不同凹模直径对封头多次成形载荷和壁厚的影响。研究结果表明,多次热冲压可以有效地降低封头的成形载荷60%左右。多次热冲压封头壁厚比一次成形稍有减薄,但最大减薄率为5.9%,在合理要求范围内。通过与相近规格封头进行实验对比,壁厚分布规律相一致,因此能够达到较好地预测成形的目的。

Once and multi - hot stamping processes of large thick-wall elliptical head were numerically simulated by finite element method. The differences of hydraulic press forming load and thickness of the head from the two forming processes were analyzed compara- tively, and the influence of different die radius on the forming load and thickness was studied. The results show that multi-hot stamping can effectively reduce the forming load to 60%. The thickness of the heads formed by multi-hot stamping is slightly thinner than that of the heads formed by one time stamping, but the biggest thinning rate is 5.9% which is in a reasonable range. Compared with the head of sim- ilar specifications, wall thickness distribution is consistent, and the goal of a better prediction of thick-wall head forming can be achieved.