Non‑associated and Non‑quadratic Characteristics in Plastic Anisotropy of Automotive Lightweight Sheet Metals

作     者：Yong Hou Junying Min Myoung‑Gyu Lee 

作者机构：Department of Materials Science and Engineering and RIAMSeoul National UniversitySeoul 08826South Korea School of Mechanical EngineeringTongji UniversityShanghai 201804China 

出 版 物：《Automotive Innovation》 (汽车创新工程（英文）)

年 卷 期：2023年第6卷第3期

页      面：364-378页

核心收录：

学科分类：082304[工学-载运工具运用工程] 08[工学] 080204[工学-车辆工程] 0802[工学-机械工程] 0823[工学-交通运输工程] 

基　　金：support of the BK21 Four program(SNU Materials Education/Research Division for Creative Global Leaders) support from the Science and Technology Commission of Shanghai Municipality(grant number:21170711200) MGL appreciates the grant from NRF(No.2022R1A2C2009315) supported by the KEIT(1415185590,20022438) funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea) 

主　　题：Yield behavior Non-associated flow rule Non-quadratic Lightweight sheet metal 

摘      要：Lightweight sheet metals are highly desirable for automotive applications due to their exceptional strength-to-density *** accurate description of the pronounced plastic anisotropy exhibited by these materials in finite element analysis requires advanced plasticity *** recent years,significant efforts have been devoted to developing plasticity models and numeri-cal analysis methods based on the non-associated flow rule(non-AFR).In this work,a newly proposed coupled quadratic and non-quadratic model under non-AFR is utilized to comprehensively investigate the non-associated and non-quadratic characteristics during the yielding of three lightweight sheet metals,i.e.,dual-phase steel DP980,TRIP-assisted steel QP980,and aluminum alloy *** materials are subjected to various proportional loading paths,including uniaxial tensile tests with a 15°increment,uniaxial compressive tests with a 45°increment,in-plane torsion tests,and biaxial tensile tests using laser-deposited arm-strengthened cruciform *** show that the non-AFR approach provides an effective means for accurately modeling the yield behavior,including yield stresses and the direction of plastic strain rates,simultaneously,utilizing two separate functions and a simple calibration *** introduction of the non-quadratic plastic potential reduces the average errors in angle when predicting plastic strain directions by the quadratic plastic potential ***,for DP980,the average error is reduced from 3.1°to 0.9°,for QP980 it is reduced from 6.1°to 3.9°,and for AA5754-O it is reduced from 7.0°to 0.2°.This highlights the importance of considering the non-quadratic characteristic in plasticity modeling,especially for aluminum alloys such as AA5754-O.