双相钢激光拼焊板温拉伸性能及微观组织  

Warm Tensile Properties and Microstructures of Dual Phase Steel Laser Tailor Welded Blanks

作　　者：陈炜[1] 薛雷[1] 陈康敏[2] 承善[1] 

机构地区：[1]江苏大学机械工程学院,江苏镇江212013 [2]江苏大学材料科学与工程学院,江苏镇江212013

出　　处：《材料工程》2010年第7期54-58,共5页Journal of Materials Engineering

基　　金：国家自然科学基金资助项目(50775102);江苏省教育厅"青蓝工程"资助项目(苏教师[2007]2号);上海市数字化汽车车身工程重点实验室开放基金课题(2008003)

摘　　要：利用温拉伸实验和金相实验,系统研究了双相钢激光拼焊板温拉伸过程中温度、拉伸性能及微观组织三者之间的相互关系。结果表明:随着温度的升高,双相钢激光拼焊板真实应力-应变曲线下降,抗拉强度降低,延伸率升高;温拉伸条件下双相钢激光拼焊板的断裂位置处于焊缝部位,且焊缝组织发生明显变化,随着温度的升高,焊缝中的树枝晶逐渐消失,板条马氏体最终转变为细小的等轴状铁素体;不同温度下焊缝拉伸断口均为韧窝断裂,且随着温度升高,韧窝尺寸变大,深度变深。The tensile properties and microstructures of dual phase steel laser tailor welded blanks（DP-LTWBS）have been investigated.The correlation of temperatures,tensile properties and microstructures has also been studied systematically.The results showed that true stress-strain curves dropped down,the tensile strength decreased and the elongation increased with the increasing temperatures.During the warm tension the cracks initiated from the weld and the microstructures changed markedly.The arborescent structure died out with the increasing temperatures,and finally lath martensite has been transformed into fine equiaxed ferrite.The tensile fracture types of the weld were dimple under different temperatures.The size and depth of dimple increased with the increasing temperature.

关 键 词：激光拼焊板 温拉伸 拉伸性能 微观组织 双相钢 

分 类 号：TG457.11[金属学及工艺—焊接] TG113