汽车前轴精密辊锻成形过程的数值模拟

NUMERICAL SIMULATION FOR PRECISION ROLL FORGING OF AUTOMOBILE FRONT AXLE

汽车前轴的精辊-模锻工艺是一种用小成形力锻造设备成形较大型前轴锻件的塑性加工技术,其工艺关键在于精密辊锻。前轴的精密辊锻分4个道次,是典型的局部成形工艺。辊锻工艺由于旋转的模具与辊锻件之间的接触区域在不断变化,一直以来成为数值模拟的难点。对4个道次的模具建立了模型,采用三维刚塑性有限元程序DEFORM-3D模拟了前轴精密辊锻工艺,分析了辊锻过程中金属变形的规律,研究了模具参数对成形质量的影响以及辊锻力矩的变化规律。模拟结果对于改进辊锻工艺设计、提高模具设计水平具有指导作用。

The precision roll forging-die forging for automobile front axle is a plastic working technology of large front axle forging by small rating forging press. The key of this technology is precision roll forging. Roll forging process of front axel includes 4 steps, which is a class successive partial plastic forming. Due to the contact areas between dies and work piece varying in forming, the simulation for this process is very difficult. The FEM (Finite element method) models for 4 process steps are modeled, and the rigid-plastic FEM program DEFO-RM-3D is used to simulation roll forging. Material deformation laws in roll forging are studied, and effects of die geometrical parameters and process design values on forming quality are investigated. Comparison between the computational results and tests results shows that the numerical simulation can predict perfectly the shapes and flaws of workpiece in rolling forging.