DP钢板应变路径多步演变下的弹塑性力学行为  

Elastoplastic Behaviors of DP Steel Sheet under Multi-step Strain Path Evolution

作　　者：廖娟 陈珊珊 薛新 向红亮[1] Juan Liao;Shanshan Chen;Xin Xue;Hongliang Xiang(School of Mechanical Engineering and Automation,Fuzhou University,Fuzhou,350116)

机构地区：[1]福州大学机械工程及自动化学院,福州350116

出　　处：《固体力学学报》2021年第1期94-106,共13页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金项目(51805087,51705080);福建省自然科学基金项目(2018J01761,2018J01764);福建省重大科技专项项目(2017HZ0001-2)资助。

摘　　要：针对DP高强双相钢板在复杂载荷作用下的弹塑性力学特征,提出利用三步拉伸力学实验,对比分析单轴循环加载和非等轴加载下材料的各向异性硬化、永久软化和弹性模量衰减特性等力学行为,揭示应变路径多步演变下的弹塑性力学特性。研究结果表明:材料再加载初期的瞬态行为与应变路径有关,在初期瞬态阶段显示出明显的各向异性,且再加载角度、预应变量以及马氏体含量的增加都会加剧两种DP钢过渡期后的应力软化行为。同时对不同加载下DP钢弹性模量的演化进行了对比,发现弹性模量的衰减程度也随着再加载角度,预应变量和马氏体含量的增加而增加,弹性模量衰减程度在多步非等轴加载比单轴循环载荷作用下表现更明显。This study aims to analyze the elastoplastic characteristics of DP steels under complex loading conditions.The three-step tensile tests associated with stain path change were proposed and conducted.The comparison of mechanical behaviors such as degradation of elastic modulus,anisotropic hardening and permanent softening between monotonic cyclic loading and non-coaxial loadings were performed and analyzed.The results show that the transient anisotropy hardening behavior of the materials at the initial stage of reloading is related to the strain path.The increase of reloading angle,pre-strain magnitude,or martensite content can exacerbate permanent softening of the materials.Meanwhile,the evolutions of elastic modulus of DP steels under different loadings were compared.It is found that the degree of elastic modulus degradation also rises with the increase of reloading angle,pre-strain magnitude,or martensite content.In addition,the results indicate that the evolution of elastic modulus degradation under complex loading path changes is more significant than that under monotonic cyclic loading.

关 键 词：DP钢 应变路径改变 各向异性 永久软化 弹性模量衰减 

分 类 号：TG142.1[一般工业技术—材料科学与工程]