摘要
通过落锤撕裂试验(DWTT)研究了厚规格多相组织X80管线钢断裂行为与微观组织之间的关系。采用OM和SEM对X80管线钢微观组织和DWTT试样断口形貌进行观察。研究结果表明,钢板微观组织由粒状贝氏体(GB)、针状铁素体(AF)、贝氏体铁素体(BF)、多边形铁素体(PF)和准多边形铁素体(QPF)构成;分层裂纹形成于带状组织处;马氏体-奥氏体(MA)岛、夹杂物周围易萌生微孔及二次裂纹;在晶粒内部形核长大的二次裂纹扩展到小尺寸MA岛及AF处会出现止裂,提高了钢板的断裂韧性。
The microstructure and fracture morphology of drop-weight tear test(DWTT)for multi-phase heavy wall X80 pipeline steel were observed by optical microscopy(OM)and scanning electron microscopy(SEM)to analyze the relationship between fracture behavior and microstructure.The results show that the microstructure of X80 pipeline steel is composed of granular bainite(GB),polygonal-like ferrite(PF),quasi-polygonal ferrite(QPF),bainitic ferrite(BF),and acicular ferrite(AF).The delamination cracks are easily generated in the banded structure,the inclusions could cause the generation of voids and secondary cracks.The secondary cracks nucleate and grow inside the grains,and are arrested on the small martensite-austenite(MA)and acicular ferrite boundaries,which improves the fracture toughness of the steel plate.
作者
王慧慧
宋开兰
左秀荣
吴翔
赵威威
Wang Huihui;Song Kailan;Zuo Xiurong;Wu Xiang;Zhao Weiwei(Key Laboratory of Material Physics,Ministry of Education,Zhengzhou University,Zhengzhou Henan 450052,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2019年第8期228-235,共8页
Heat Treatment of Metals
基金
河南省科技开放合作项目(182106000016)
关键词
X80管线钢
分层裂纹
带状组织
MA岛
粒状贝氏体
X80 pipeline steel
delamination cracks
banded structure
martensite-austenite constituents
granular bainite
