EH36船板用钢探伤不合格原因分析  

Cause analysis of unqualified flaw detection for EH36 ship plate steel

作　　者：张欢 张渊普 王孝东 余宏伟 张开广 ZHANG Huan;ZHANG Yuanpu;WANG Xiaodong;YU Hongwei;ZHANG Kaiguang(Echeng Iron&Steel Co.,Ltd.,Baowu Group,Ezhou 436002,China;Central Research Institute,Baowu Group,Wuhan 430080,China)

机构地区：[1]宝武集团鄂城钢铁有限公司,湖北鄂州436002 [2]宝武集团中央研究院,湖北武汉430080

出　　处：《物理测试》2022年第5期50-55,共6页Physics Examination and Testing

摘　　要：为找出EH36船板用钢探伤不合格的原因,将探伤不合格的钢板通过人工探伤缺陷定位取样,通过光谱仪、光学显微镜、电子探针等仪器,对试样的成分、组织进行分析,结果表明:EH36钢板基体组织为铁素体和珠光体,裂纹附近C、Mn、P元素偏析严重,且有大尺寸的MnS夹杂和高度富集的(Ti, Nb, V)化合物出现,裂纹开口处有马氏体和贝氏体异常组织形成。通过适当控制钢中S、P含量,优化精炼、连铸和加热工艺,可减轻铸坯中心偏析程度;采用细晶轧制和弱冷相结合,可抑制马氏体组织形成。综合以上措施可提高钢板探伤合格率。In order to find out the reason for the unqualified flaw detection of EH36 ship plate steel, the unqualified steel plate was fixed for sampling by manual inspection. The composition and structure of the sample were analyzed using spectrometer, optical microscope, and electron probe. The results show that the matrix structure of EH36 steel plate is composed of ferrite and pearlite. The segregation of C, Mn and P near the crack was severe. Moreover, there were large-size MnS inclusions and highly enriched(Ti, Nb, V) compounds. The abnormal microstructure of martensite and bainite was formed at the crack opening. By properly reducing S and P contents in steel, and optimizing the processes including refining, continuous casting and heating, the degree of central segregation in casting blank could be reduced. The combination of fine grain rolling with weak cooling could inhibit the formation of martensite structure. The qualified rate of flaw detection for steel plate could be improved through the above comprehensive measures.

关 键 词：船板用钢 探伤 中心偏析 马氏体 裂纹 

分 类 号：U672[交通运输工程—船舶及航道工程] TG142.1[交通运输工程—船舶与海洋工程]