丁字臂锻件裂纹分析及工艺改进

Crack analysis and process optimization of T-shaped arm forgings

为解决实际生产中丁字臂锻件直孔端附近出现的裂纹问题,基于数值模拟对相应的温度场、等效应变场和速度场进行分析,认为直孔端附近材料的流动速度快且梯度大可能是引起裂纹的主要原因。在此基础上,提出了增设阻力沟的飞边结构设计和一模两件锻模设计的两种改进方案。结果表明,增设阻力沟可有效地降低直孔端处桥部飞边的流动速度,但是无法改变其流动速度不断增大的趋势;一模两件工艺方案,改变了直孔端的金属流动模式,改善了危险区域流动均匀性并获得较为均匀的温度场。后续将安排实际工艺试验,进一步开展验证工作。

To solve the crack problem near the end of straight hole for T-shaped arm forgings in actual production,the corresponding temperature field,equivalent strain field and velocity field were analyzed by numerical simulation,and it was believed that the high flow velocity with large gradient of material near the end of straight hole might be the main reason to crack. According to this,two improved schemes of the flash structure design with resistance groove and the forging die design of two-cavity were proposed. The results show that adding the resistance groove could effectively reduce the flow velocity of material for bridge flash at the end of straight hole,but it could not change the increasing trend of flow velocity. The process design of die with two-cavity could change the flow pattern of metal at the end of straight hole,improve the flow uniformity in the dangerous area and achieve a relatively homogeneous temperature field. The actual process experiment will be arranged in the future to carry out verification work.