Effect of Pre-strain on Microstructure and Stamping Performance of High-strength Low-alloy Steel  

作　　者：刘坡 WEN Zhicheng LIU Zheng 许峰 LIU Po;WEN Zhicheng;LIU Zheng;XU Feng(School of Mechanical Engineering,Guilin University of Aerospace Technology,Guilin 541004,China;School of Automotive Engineer-ing,Changshu Institute of Technology,Changshu 215500,China)

机构地区：[1]School of Mechanical Engineering,Guilin University of Aerospace Technology,Guilin 541004,China [2]School of Automotive Engineer-ing,Changshu Institute of Technology,Changshu 215500,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2024年第3期774-780,共7页武汉理工大学学报（材料科学英文版）

基　　金：Funded by Natural Science Foundation of Guangxi Zhuang Autonomous Region(No.2020JJA160034);the Basic Ability Improvement of Middle and Young Teachers in Guangxi Universities Foundation(No.2020KY21018)。

摘　　要：In this study,pre-strain ranging from 0 to 0.12 was applied through uniaxial tension on high-strength low-alloy(HSLA)specimens with four kinds of grain size.Effect of pre-strain and grain size on me-chanical property was investigated through tensile tests.Microstructures of the pre-strained and tensile tested samples were analyzed,respectively.The 30.8°v-bending and following flattening,as well as Erichson cupping tests,were performed on the pre-strained samples.Results show the elongation ratio of grain and dislocation density increases with pre-strain.Yielding platform is removed when pre-strain is larger than 0.06 while yielding plateau period decreases with pre-strain less than 0.06 due to reduction of pinning effect.The 30.8°v-bending and the following flattening tests are successfully accomplished on all the pre-strained samples with different grain size.Decrease in grain size,along with increase in pre-strain,causes increase in strength and decrease in elongation rate as well as cupping value.Pre-strain causes very slight effect on bending ability,much less than that on mechanical property and cupping test value.Reciprocal impact of the pre-strain and grain size on HSLA steel deformability is inconspicuous.

关 键 词：strain hardening DISLOCATION TEXTURE BENDING erichson cupping test 

分 类 号：TG142.33[一般工业技术—材料科学与工程]