汽车转向节差压铸造及淬火过程应力应变场数值模拟

Simulation of Stress and Strain Field in Counter-Pressure CastingQuenching Process of Automotive Steering Knuckle

针对汽车转向节结构复杂、制造困难以及实际生产工艺设计过程中很难做到对应力应变的定量分析的问题,采用ProCAST软件进行数值模拟,并通过实测温度与数值模拟结果对比,验证了温度场计算的准确性。采用热力耦合的数值模拟方法,对汽车转向节差压铸造-空冷-淬火过程进行动态数值模拟,得到了铸件的温度/应力/应变的动态变化及分布规律。采用蓝光扫描仪对汽车转向节铸件的轮廓进行测定,利用Geomagic Control拟合软件对铸件实际变形进行分析。数值模拟与实测得到铸件的最大变形量分别为2.85 mm和3.25 mm,铸件变形分布规律基本一致。本研究为避免汽车转向节铸件出现大的残余应力区、预设反变形量、改善铸造工艺提供了量化参考依据。

Due to the complexity of the structure of the steering knuckle and its difficulty in manufacturing,it is difficult to quantify the stress and strain during the design and production.In this study,the ProCAST software was applied to simulate the residual stress distribution of castings,and the accuracy of the temperature field calculation was verified by comparing the measured data with the numerical simulated results.The dynamic simulation of casting-air cooling-quenching process of automobile steering knuckle was carried out by thermo-mechanical coupling.The dynamic variation and distribution of temperature/stress/strain in the whole production process were obtained.The profile of automobile steering knuckle castings was measured by bluelight scanner.The actual deformation of the castings was analyzed by Geomagic Control fitting software.Results show that both the simulated and measured deformation basically follows the same rule and their maximum deformation are 2.85 mm and 3.25 mm,respectively.This study provides quantitative reference for avoiding large residual stress zone,presupposing reverse deformation and improving casting technology of automobile steering knuckles.