摘要
通过JMatpro软件、扫描电镜、力学性能测试,对Q500qE 60 mm厚度500 MPa级低屈强比高强钢板进行了连续冷却转变(CCT)曲线、钢板显微组织与力学性能、焊接接头力学性能分析。结果表明,通过控轧控冷工艺:终轧温度800~840℃,入水温度660~680℃和终冷温度400~450℃,该钢组织为铁素体+贝氏体+马氏体/奥氏体岛,两相交界处和贝氏体内部存在大量大角度晶界。钢板1/4和1/2厚度位置屈服强度≥500 MPa,抗拉强度≥640 MPa,屈强比≤0.80,-40℃低温冲击功≥200 J,焊接热影响区-40℃低温冲击功≥100 J。
The continuous cooling transformation(CCT)curve,microstructure and mechanical properties of Q500qE low yield ratio high strength steel 60 mm thickness plate have been studied by JMatpro software,scanning electron microscope and mechanical property tests.The results show that by control rolling and control cooling process:the final rolling temperature 800-840℃,the into water temperature 660-680℃and the final cooling temperature 400-450℃,the microstructure of steel is composed of ferrite,bainite and MA(martenite/austenite)island,and many large angle grain boundaries exist in junction of two phases and in bainite.The properties of the steel at 1/4 and 1/2 thickness are yield ratio 0.78-0.79,yield strength≥500 MPa,tensile strength≥640 MPa,charpy impact energy of 1/2 thickness at-40℃≥200 J,for HAZ charpy impact test at-40℃,the charpy impact energy of HAZ≥100 J.
作者
孙宪进
杜鹏举
赵乾
Sun Xianjin;Du Pengju;Zhao Qian(Insitute of Research of Special Steel,JiangyinXingcheng Special Steel Co.,Ltd.,Jiangyin 214400)
出处
《特殊钢》
2022年第5期74-77,共4页
Special Steel
关键词
低屈强比
多相组织
Q500qE高强钢板
60
mm厚板
Low Yield Ratio
Multi-Phases Microstructure
Q500qE High Strength Steel
60 mm Thickness Plate
