2124铝合金热变形机理分析及冲压工艺参数优化

Analysis of Thermal Deformation Mechanism of 2124 Aluminum Alloy and Optimization of Stamping Process Parameters

为了研究2124铝合金的热变形性能,在不同温度与应变率条件下进行了热拉伸试验,获得材料应力-应变曲线。针对2124铝合金热变形特点,基于汉森-斯皮特尔模型建立了该材料的本构模型,并通过遗传算法优化模型参数。开发了汉森-斯皮特尔本构模型的ABAQUS用户材料子程序VUMAT,并将其用于双C件冲压成形分析。以冲压速度、压边力、摩擦系数和温度作为设计变量,成形件最大减薄率作为响应值建立Kriging代理模型,采用遗传算法对工艺参数进行优化。双C件热冲压试验结果表明,优化的工艺参数可以消除板料成形开裂缺陷,验证了本构模型与有限元模型的可靠性。

In order to study the hot forming performance of 2124 aluminum alloy, the hot tensile experiments under different temperature and strain rate conditions were carried out and the material’s stress-strain curves were obtained. Aiming at the hot forming characteristics of 2124 aluminum alloy, the constitutive model of the material was established based on the Hansen-Spitel model, and the model parameters were optimized by genetic algorithm. The ABAQUS user material subroutine VUMAT of the Hansen-Spitel constitutive model was developed, and it was applied for the analysis of double C stamping parts. The stamping speed, blank holder force, friction coefficient and temperature were regarded as design variables, and the maximum thinning rate of the forming parts was regarded as the response value to establish the Kriging surrogate model, and the genetic algorithm was used to optimize the process parameters. The hot stamping experiment results of double C parts show that the optimized process parameters can eliminate the sheet metal forming cracking defects, and it verifies the reliability of the constitutive model and the finite element model.