轴承套圈锻造过程的计算机仿真研究

本文运用MSC-Marc软件对轴承锻造加工过程进行了计算机仿真.以金属成形理论和有限元方法基本原理为基础,建立了热力偶合刚粘塑性轴承锻造模型.包括对材料特性进行了完整的描述,确定了成形模拟中体积不可压缩实现方法.以二代轮毂轴承外圈锻造为例进行模拟分析.模拟分析中进行了冲头力的计算及对两次预成形模型的实验和模拟结果的对比;提出了产生过大冲头力的一个原因是最终成形阶段工件在模腔内分布不均使变形速率急剧增加;分析了工件应力和模具结构的关系及其优化问题,对冲头的倒角圆弧半径作了优化;对温度效应、表面质量和金属流线等锻造设计有关问题作了讨论.提出了预成形坯的设计优化准则,以此设计了二代轮毂轴承外圈的优化的预成形结构,冲头力比原设计下降了一半以上.

Digital Simulation for the Forging Process of Bearing Ring

Using MSC-Marc for the analysis of bearing ring forging process is presented in this paper. Based on the principles of the theory of metal forming and FEM, a thermal-mechanical coupled rigid-viscoplastic model for forging is created,including the definition of the properties of material and the realization of incompressibility of material. As an example, the forging of the second-generation hub bearing outer-ring is analyzed. The punch force is computed and the results of trial making and of analysis for two pre-formed work-piece designs are compared; the reason of rising of the punch force is that work-piece is unevenly distributed in the tools space at final stage of forming leading to increasing of stress rate; the relation of the stress of the work-piece and that of tools is analyzed, and optimized with an example for the punch rounding radius; other forging process design elements, like the temperature setting, surface quality and metal flow-line are also discussed. The criterion for the design of optimized pre-formed work-piece is created, and based on which, an optimized pre-formed work-piece is designed with the result of punch force of only less than half of that of previous designs.