数值模拟技术在汽车覆盖件成形中的应用

金属薄板成形的数值模拟技术在汽车覆盖件生产及其模具设计制造中起着十分重要的作用。数值模拟技术的广泛应用可以帮助模具设计人员显著地减少模具开发时间、试模周期和费用。为此，详细介绍了应用Dynaform软件模拟覆盖件成形过程的一般步骤，并以某汽车覆盖件的拉深为例，对其成形过程进行了数值仿真。通过对模具零件的运动、板料的成形，以及板料厚度的变化，应力应变分布，成形极限预测等结果的分析，进一步弄清了板料形状，压料筋布置以及压边力大小等工艺参数对汽车覆盖件质量的影响。在案例分析的基础上，针对覆盖件坯料拉深过程中可能出现的起皱现象，给出了相应的拉深工艺优化和模具方案优化。

Application of numerical simulation in automobile covering parts forming process

The technique of numerical simulation in forming automobile covering parts and designing the moulds plays an important role. The technique of numerical simulation is comprehensively used, which can dramatically help mould designers to reduce the development time of the die, the periodic time of debugging the die and the cost. So this paper particularly introduces the general step of simulation about covering parts forming by using Dynaform software. Taking the drawing process of a certain automobile covering part as an example, the numerical simulation of forming process is achieved. By the analysis of the movement of the die, the forming of the blank, the change of the thickness of the blank, the distribution of the stress and strain and the forecast of forming limit, the impact of the shape of the blank, the layout of the drawbead and the value of the binder force on the quality of the automobile covering part is clarified. On the basis of analyzing a typical case, the corresponding programs which can optimize the forming plan and mould design for solving wrinkle problem that may appear in drawing process of the blank of covering parts are also presented in this paper.