双层板汽车消声器外壳成形工艺分析及仿真

摘要

针对不锈钢双层板汽车消声器外壳成形中出现的起皱和破裂问题,从产品结构特点上详细地分析了可能产生问题的原因,提出了多种解决问题的成形工艺方案,并通过有限元数值仿真对其进行了模拟和对比分析.结果表明,对双层板采用点焊连接,并设置局部拉延筋和变压边力的成形工艺能够使得成形时材料流入均衡、改善凹筋弯曲处的受力状况,从而有效地解决汽车消声器外壳中凹筋弯曲处的起皱和拉伸深度过大端破裂的问题.%To solve the problem of wrinkle and crack in sheet metal forming for bimetal laminated stainless auto-muffler cover,the structural feature of the product was analysed in detail to identify the cause,several forming process schemes were then proposed based on that, and finite element simulations of those schemes were also taken and compared each other. Results show that, the process scheme of welding the bimetal laminated sheet ..setting the local drawbead and adopting the varible blankhold force would make the material flow evenly into the mold、improve the stress state of the reinforced rib,and eventually prevent the product from wrinkling especailly in the bend area of reinforced rib, solve the problem of cracking in the deep draw position.