基于DIC技术的不同汽车用板材成形性能评估  

Formability Assessment of Different Materials for Automotive Sheets Based on DIC Technology

作　　者：纪登鹏 连昌伟 刘兵 JI Dengpeng;LIAN Changwei;LIU Bing(Research Institute of Baosteel,Shanghai 201900,China;State Key Laboratory of Development and Application Technology of Automotive Steels(Baosteel),Shanghai 201900,China;Quality Assurance Department Centre Laboratory,SAIC Motor Passenger Vehicle Co.,Shanghai 201804,China)

机构地区：[1]宝钢股份有限公司中央研究院,上海201900 [2]汽车用钢开发与应用技术国家重点实验室(宝钢),上海201900 [3]上海汽车集团股份有限公司乘用车分公司质量保证部中心实验室,上海201804

出　　处：《机械工程材料》2023年第6期78-85,共8页Materials For Mechanical Engineering

摘　　要：利用万能材料试验机对多种汽车用板材,包括不同强度级别的先进高强钢、传统高强钢、铝合金板材进行室温拉伸试验,采用数字图像相关(DIC)技术获取材料在拉伸过程中的全场应变,对比了不同板材的成形性,讨论了材料成形性能的评估方法。结果表明:汽车用板材的断裂应变整体上远大于断裂总延伸率,相比于断裂总延伸率,断裂应变与强度更符合负相关的关系;最大力总延伸率反映材料的硬化与均化应变的能力,不是塑性的直接指标,断裂应变表征材料的真实塑性;成形性指数综合考虑了硬化能力与真实塑性,相比于单一的延伸率指标能更好地评价材料的成形性。Room temperature tensile tests were conducted on a variety of materials for automotive sheets,including advanced high strength steel with different strength levels,traditional high strength steel and aluminum alloy sheet,by using a universal material testing machine.The full-field strain of the materials during tension was obtained by digital image correlation(DIC)technology.The formability of different sheets was compared,and the evaluation method of material formability was discussed.The results show that the fracture strains of the materials for automotive sheets were much larger than the percentage total extension at fracture in general.Compared with the percentage total extension at fracture,the fracture strain was more negatively correlated with the strength.The percentage total extension at maximum force reflected the ability of hardening and strain homogenization of materials,and was not the direct index of plasticity.The fracture strain represented the true plasticity of materials.The formability index took into account both the hardening ability and the true plasticity,and could evaluate the formability of the material better than the single elongation.

关 键 词：数字图像相关 硬化能力 真实塑性 整体成形性 局部成形性 

分 类 号：TG115[金属学及工艺—物理冶金]