高强钢拼焊板薄壁结构耐撞性数值仿真研究

Numerical study on crashworthiness of thin-walled structures of tailor welded blanks(TWBs)with high strength steel(HSS)

文章比较了多应变率处理方式以及不同焊缝模型等因素对单帽型拼焊板结构碰撞结果的影响,对比了焊缝位置和焊点间距等特征参数对其耐撞性的影响。研究考虑3种不同高强度钢的拼焊组合并对比其耐撞特性。结果表明,不同的拼焊材料和厚度会直接导致不同的碰撞变形模式和加速度曲线波形;多应变率曲线能够获得更好的仿真精度;无论是同材异厚组合、异材同厚组合还是异材异厚组合,采用共节点或者刚性连接来模拟焊缝是较为合适的;在保证吸能的条件下,尽可能加大前端区域能够获得更理想的加速度曲线;在保证焊点不发生断裂的条件下,焊点间距或者焊点数目仅影响峰值大小及时刻,并不影响加速度曲线变化的总体趋势。

The effects of different treatment methods of strain rate curves and weldline models on crashing performance were compared.Then the effects of the weldline locations and the spotwelds distances were performed considering three different TWBs combinations.The compared results show that different material and thickness would directly lead to different deformed modes and acceleration curves.By the comparison,the multi-curves of different strain rates are more accurate,and conode or rigid link method is thought as suitable whichever welding combination is.Furthermore,if the fracture of spotweld is neglected,the spotweld distances or number of spotwelds affect the peak acceleration values and their corresponding time,and do not affect their change trends.