回火温度对淬火后1500 MPa级热成形钢力学性能和组织的影响  

Effect of tempering temperature on the mechanical properties and microstructures of 1500 MPa hot stamping steel after quenching

作　　者：王子健 黄伟 彭则 梁肖 邓建林 Wang Zijian;Huang Wei;Peng Ze;Liang Xiao;Deng Jianlin(Jiangxi Hot Stamping Automotive Component Co.,Ltd.,Jiujiang 332400,Jiangxi,China;Sochoow University,Suzhou 215031,Jiangsu,China)

机构地区：[1]江西豪斯特汽车零部件有限公司,江西九江332400 [2]苏州大学,江苏苏州215031

出　　处：《钢铁钒钛》2024年第6期172-176,共5页Iron Steel Vanadium Titanium

基　　金：国家自然科学基金青年基金项目(51905189);国家科技重大专项项目(2018ZX04023001)。

摘　　要：针对1 500 MPa级热成形钢进行淬火和回火处理,利用金相显微镜、室温拉伸检测和扫描电镜等方法研究回火温度对材料显微组织和力学性能的影响。结果表明:Cr含量过高,会降低C的活度,抑制渗碳体的形成,因此钢中主要碳化物为M23C6和M7C3类,随着回火温度提高到400℃左右,碳化物会由M23C6类转化为M7C3类;抗拉强度、屈服强度和硬度随着回火温度的升高逐渐降低,当回火温度超过400℃之后强度会显著降低,延伸率随着回火温度的升高逐渐升高,而强塑积随着回火温度的升高呈现先增大后减小的趋势;板条马氏体中存在的高密度位错会随着回火温度的升高而下降,马氏体板条会相互吞噬、合并,逐渐模糊,基体中出现铁素体,此外碳化物也会析出并长大。Quenching and tempering treatment were carried out on a 1500 MPa hot formed steel,and the effects of tempering temperature on the microstructures and mechanical properties were studied using methods such as metallographic microscopy,room temperature tensile testing,and scanning electron microscopy.The results show that if the Cr content is too high,it will reduce the activity of C and inhibit the formation of carbides.Therefore,the main carbides in the steel are M23C6 and M7C3.As the tempering temperature increases to around 400℃,the carbides will transform from M23C6 to M7C3,and the tensile strength,yield strength,and hardness will gradually decrease with the increase of tempering temperature.When the tempering temperature exceeds 400℃,the strength will significantly decrease,the elongation will gradually increase by enhancing tempering temperatures.The strength plastic product will first increase and then decrease with the increase of tempering temperature.The high-density dislocations in Flat noodles martensite will decrease,and the martensite will engulf and merge with each other,and then gradually blur with the increase of tempering temperature.Ferrites appear in the matrix.In addition,carbides will also precipitate and grow up.

关 键 词：1500 MPa级热成形钢 回火 碳化物 马氏体板条 

分 类 号：TF76[冶金工程—钢铁冶金] TG156[金属学及工艺—热处理]