高压铸铝合金本构模型和断裂准则研究  

STUDY ON CONSTITUTIVE MODEL AND FRACTURE CRITERION OF HIGH PRESSURE CAST ALUMINUM ALLOY

作　　者：张明辉 魏广凯 李伦操 杨斌 付昆昆[1] ZHANG Ming-hui;WEI Guang-kai;LI Lun-cao;YANG Bin;FU Kun-kun(School of Aerospace Engineering and Applied Mechanics,Tongji University,Shanghai 200082,China)

机构地区：[1]同济大学航空航天与力学学院,上海200082

出　　处：《工程力学》2025年第4期234-245,共12页Engineering Mechanics

基　　金：国家自然科学基金项目(12172257);国家自然科学基金青年项目(12102303)。

摘　　要：高压铸铝合金是实现结构轻量化最常用的轻质合金材料之一,其本构关系和断裂准则是结构安全性设计的关键。为了探索高压铸造铝合金ZTHJ01在准静态下的本构模型和断裂准则,设计了高压铸造铝合金标准拉伸、R5缺口拉伸、中心孔拉伸、平面剪切、蝴蝶剪切和三点弯曲六种实验样件,结合数字图像相关法(Digital Image Correction,DIC)开展了试验测试。根据对应力-应变曲线外推两种不同混合性硬化准则,准确描述了高压铸铝合金的应变硬化特性。提出有限元仿真模型,获得了不同应力状态下断裂应变与应力三轴度和Lode角参数的相互关系,构建并标定了修正的Mohr-Coulomb断裂准则和Hosford-Coulomb断裂准则参数。通过杯突试验和有限元仿真模拟验证了不同硬化准则下断裂模型的有效性。结果表明:两种不同硬化准则下的修正Mohr-Coulomb和Hosford-Coulomb断裂准则都可较好的实现对高压铸铝合金断裂失效的准确预测,其中,Swift-Voce硬化准则下的修正Mohr-Coulomb断裂模型表现出更高的精度。High pressure cast aluminum alloy is one of the most commonly used lightweight alloy materials to realize structural lightweight.Its constitutive relation and fracture criterion are key to structural safety design.To explore the constitutive model and fracture criterion of high-pressure casting aluminum alloy ZTHJ01 under quasi-static state,six experimental specimens of high-pressure casting aluminum alloy,including standard tensile,R5 notch tensile,central hole tensile,plane shear,butterfly shear and three-point bending,were designed and tested in combination with Digital Image Correction(DIC).According to the stress-strain curve,two different mixed hardening criteria are extrapolated,and the strain hardening characteristics of high-pressure cast aluminum alloy are accurately described.The finite element simulation model is proposed,and the relationship between fracture strain and stress triaxiality and Lode angle parameters under different stress states is obtained.The Modified Mohr-Coulomb(MMC)fracture criterion and Hosford-Coulomb(HC)fracture criterion parameters are constructed and calibrated.The effectiveness of the fracture model under different hardening criteria is verified by cupping test and finite element simulation.The results show that the MMC and HC fracture criteria under two different hardening criteria can better predict the fracture failure of high-pressure cast aluminum alloy,and the MMC fracture model under swift voce hardening criteria shows higher accuracy.

关 键 词：高压铸铝 本构模型 修正Mohr-Coulomb断裂准则 Hosford-Coulomb断裂准则 数值模拟 

分 类 号：TG115.5[金属学及工艺—物理冶金] U465.22[金属学及工艺—金属学]