两相区淬火温度对Ni-Cr-Mo-V系高强船体钢组织及性能的影响  

Effect of intercritical quenching temperature on micro-structure and properties of Ni-Cr-Mo-V high strength hull steel

作　　者：郭天阳 罗小兵[2] 项重辰 丁汉林 柴锋[2] 潘涛[2] GUO Tianyang;LUO Xiaobing;XIANG Chongchen;DING Hanlin;CHAI Feng;PAN Tao(School of Iron and Steel,Soochow University,Suzhou 215021,China;Institute for Structural Steel,Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]苏州大学沙钢钢铁学院,江苏苏州215021 [2]钢铁研究总院工程用钢研究所,北京100081

出　　处：《材料科学与工艺》2024年第3期10-17,共8页Materials Science and Technology

基　　金：中央高校基本科研业务费专项资金资助(WK2090050018)。

摘　　要：为改善高强船体钢高屈强比、回火区间窄的问题,研究了两相区二次淬火温度对Ni-Cr-Mo-V系高强船体钢组织及性能的影响。通过改变二次淬火温度,研究实验钢冲击拉伸性能和显微组织的变化规律,并通过OM、TEM、XRD衍射等方法进行表征。结果表明,在淬火温度区间内,材料的性能表现出两种变化趋势。当淬火温度在640~700℃时,实验钢的强度随着二次淬火温度的上升而增加,而韧性下降。在该淬火温度范围内,实验钢的机械性能由铁素体+马氏体的双相组织和逆转变奥氏体的含量决定。随着二次淬火温度的上升,双相组织中铁素体的比例从40%降至10%,逆转变奥氏体的含量从11%下降至1%。当二次淬火温度从700℃增加到780℃时,实验钢的强度和韧性变化不明显,原因是二次淬火的温度已经超过了A3温度,实验钢组织转变为单一的马氏体组织,奥氏体晶粒尺寸变化不大(7.3~8.5μm)。综上,在680℃下进行两相区二次淬火可以获得最佳的强度和韧性匹配。To improve the high yield ratio and narrow tempering range of high strength hull steel,the effect of intercritical quenching temperature on the microstructure and properties of Ni-Cr-Mo-V steel was investigated.The impact tensile properties and microstructure of the experimental steel were examined by changing the secondary quenching temperature,and characterized by MO,TEM,X-ray diffraction and other methods.The results show that in quenching temperature range,the properties of the material show two phenomena:when the quenching temperature between 640 to 700℃,the strength of steel increases with the increase of intercritical temperature,and the toughness decreases.In this quenching temperature range,the mechanical properties of the material are determined by the composition of F&M microstructure and the formation of reversed austenite.With the increase of the intercritical quenching temperature,the proportion of F in the dual phase structure decreases from 40%to 10%and the content of reversed austenite reduces from 11%to 1%.When the quenching temperature varies from 700 to 780℃,the change of strength and toughness of test material is not obvious.The main reason is that the intercritical quenching temperature exceeds the A3 temperature,the steel transforms into a single martensite structure after cooling,and the change of austenite grain size is not significant,specifically between 7.3~8.5μm.The results show that the best match of strength and toughness can be achieved by intercritical quenching at 680℃.

关 键 词：两相区淬火 强度 韧性 屈强比 逆转变奥氏体 

分 类 号：TG113.1[金属学及工艺—物理冶金] TG113.2[金属学及工艺—金属学]