大规格电镦技术研究方法及研究目标的新突破及进展

New Breakthrough and Progress of Research Methods and Objectives about Large Size Electric Upsetting Technology

介绍了电镦研究方法及目标,就电镦研究现状,提出了从微观控制角度改进大规格电镦技术,在避免几何缺陷的同时,综合考虑电镦件的晶粒均细化。运用MSC.Marc有限元模拟分析软件平台自主开发子程序,建立了气阀件的电镦锻多物理场动态耦合有限元模型,通过构建电镦件晶粒度及不均匀度双目标函数,进行了气阀在具体方案下的有限元仿真监控,设计出了大规格气阀件的电镦电流非线性加载模式。进一步比较了该气阀件在优化前后晶粒度及不均匀度双目标函数值变化,以及其晶粒度与动态再结晶体积分数分布等色云图。结果表明:优化后的双目标函数值较优化前减小,优化前后的坯料均发生完全动态再结晶;但优化后坯料平均晶粒度为104.33μm,较优化前降低了26.29μm,优化后坯料晶粒度尺寸分布更加均匀。

The research methods and objectives about electric upsetting were introduced briefly and the improvement coming from the micro control perspective of large size electric upsetting technology was proposed based on the current research. Ensure that parts with electric upsetting attain homogenized and fine grain while avoiding geometrical defects. The FEM for valves with electric upsetting,a multi- field coupling technology,was established in virtue of essential secondary development of the finite element simulation software MSC. Marc. And the electric upsetting current with nonlinear loading was further designed on the basis of finite element simulation monitoring for valves under the concrete scheme after the objective function about double target including grain size and inhomogeneous distribution was constructed. A further comparison of the valve parts in the value of double target and the isochromatic nephogram of grain size and the volume fraction of dynamic recrystallization showed that the objective function value was reduced after the optimization and the average grain size after optimization was 104. 33 μm and reduced by 26. 29 μm though full dynamic recrystallization occurred. The results show that valve blank acquire more uniform distribution.