模压强化工艺及其数值仿真

Die Formed Strengthing Process and Its F.E Simulation

对模压强化工艺过程进行有限元数值仿真过程中,利用普通的有限元模型无法真实地模拟压模对先模压端面凸起部分的挤压过程,从而无法真实地再现模压强化的过程,也就无法可靠地模拟强化后的残余应力、应变场,并且该部分节点由于与接触体脱离往往会造成计算收敛困难。文中基于对实际模压工艺过程的观察,利用相对运动原理,在后端面模压工序前加了一个上工作台压向压模和工件的工况,解决了这个问题,且有限元计算结果和实测数值一致。

In the course of simulation of die formed strengthing process,it is hard,even impossible for the model built on the general thinking to take the raised material into account.Accordingly the results obtained from that model can not reproduce the real process of the strengthing process,saying nothing of the residual stress field induced by the strengthing process.Is more worse that the sliding nodes make the analysis difficult to converge.Based on the relative motion theory,a loadcase is added before the harding of the lower head surface to describe the push of upper operating platform toward the die and the workpiece.The agreement of finite element method and experimental results is good enough.