基于ABAQUS加载方式对零件加工过程材料性能影响分析  

Influence Analysis of the Loading Method on Material Performance in the Part Processing Process Based on ABAQUS

作　　者：李秀芬[1] 李鑫[1] 张永学[1] LIXiu-fen;LI Xin;ZHANG Yong-xue(Huanghe Science&Technology College,He*nan Zhengzhou 450006,China)

机构地区：[1]黄河科技学院,河南郑州450006

出　　处：《机械设计与制造》2023年第3期151-155,共5页Machinery Design & Manufacture

基　　金：河南省科技发展计划项目(192400410223)。

摘　　要：汽车用材加工过程复杂,加载方式并非一次直接加载过程,而是存在预加载的过程,采用单向拉伸获取的力学性能对其成形性进行评价误差较大。选取TRIP690作为研究材料,根据实际生产参数和实验条件,采用单向拉伸过程预应变方式,对单轴拉伸试样施加不同大小的预应变,主要为0%、5%、10%、15%等预应变量,紧接着再进行拉伸试验直至断裂失效,借此来评价材料在零件加工过程材料性能及变化规律;基于ABAQUS建立TRIP690体积元模型,模拟拉伸过程,获取残余奥氏体转变情况。对比分析结果可知:整个过程中,材料的强度均有所增加;在预应变后的继续拉伸阶段,TRIP效应不再明显;材料的初始加工硬化指数随着预应变量的增加而减小,瞬时加工硬化指数也呈现出相同的变化趋势;随着预应变量地增加,初始加工硬化指数降低,瞬时加工硬化指数呈现相同的变化趋势;在初始阶段加工硬化曲线下降到最低点,不施加预应变的试样加工硬化曲线最低点高于施加预应变的试样;软相铁素体在前期的塑性应变较高而随着应变量的增大,铁素体发生明显的加工硬化,与贝氏体的强度差减小,应变集中程度降低;试验过程和结果为成形过程分析提供参考。The process of automobile material processing is complex,not a direct loading process,which is a pre-loading process,and the mechanical properties obtained by unidirectional stretching have a large error in evaluating its formability. TRIP690 is selected as the research material. According to the actual production parameters and experimental conditions,the pre-strain method in the unidirectional stretching process was used to apply different sizes of pre-strain to the uniaxial tensile specimens,mainly 0%,5%,10%,15% and other pre-strain variables. A tensile test until fracture failure was followed,to evaluate the performance and change of the material during the forming process. Based on ABAQUS,the TRIP690 volume element model was established to simulate the tensile process and obtain the residual austenite transformation. The comparative analysis results show that the strength of the material has increased throughout the process. The TRIP effect is no longer obvious during the continued stretching stage after pre-strain. The initial work hardening index of the material decreases with the increase of the pre-strain variable,the instantaneous work hardening index also showed the same trend. As the pre-stress variable increased,the initial work hardening index decreased,and the instantaneous work hardening index showed the same trend. At the initial stage,the work hardening curve dropped to the lowest point,no pre-application. The lowest point of the work hardening curve of the strained sample is higher than that of the pre-strained sample. The plastic strain of the soft phase ferrite is higher in the early stage,and as the strain increases,the ferrite undergoes significant work hardening. The difference in strength of the austenite decreases and the degree of strain concentration decreases. The test process and results provide a reference for the analysis of the forming process.

关 键 词：汽车零件 加载方式 工艺参数 预应变 成形性 力学特性 

分 类 号：TH16[机械工程—机械制造及自动化] TG142.1[一般工业技术—材料科学与工程]