X80管线钢的组织与性能研究  

Microstructure and Mechanical Properties of Pipeline Steel X80

作　　者：衣海龙[1] 杜林秀[1] 王国栋[1] 刘相华[1] 

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110004

出　　处：《东北大学学报（自然科学版）》2008年第2期213-216,共4页Journal of Northeastern University(Natural Science)

基　　金：国家高技术研究发展计划项目(2003AA33G010);国家自然科学基金资助项目(50271015)

摘　　要：利用光学显微镜、扫描电镜、透射电子显微镜等对X80级别管线钢的组织与性能进行了研究．实验结果表明，通过控轧控冷工艺轧制的16mm厚的X80管线钢的屈服强度达到670MPa以上时，其屈强比低于0．85，韧脆转变温度低于-60℃，达到了很好的强韧性匹配．细化的针状铁素体有效地改善了实验钢的强度及韧性．X80管线钢中存在两种典型的析出物，一种以Nb，Ti（CN）为主，尺寸较大（50--200nm）；另一种以NbC为主，尺寸细小（小于30nm）．这些纳米级析出物对钢的组织细化和强化起到了重要作用．The microstructure and mechanical properties of pipeline steel X80 were investigated by means of optical electron microscope, scanning electron microscope, transmission electron microscope, etc. The experimental results showed that the yield strength of pipeline steel X80 with 16mm wall thickness can be up to over 670 MPa through controlled rolling/cooling, and the ratio of tensile strength to yield strength and ductile-brittle transition temperature are lower than 0.85 and - 60℃, respectively, thus providing a nice match between strength and toughness. Fine acicular ferrite has good effect on both the strength and toughness of the steel. Two kinds of precipitates were observed in the steel, where the coarse ones are mainly the Nb and Ti （CN） ranging from 50nm to 200 nm, and the fine ones are mainly NbC less than 30 nm. Both the nano-precipitates play an important role in strengthening and grain refinement of the steel.

关 键 词：X80管线钢 控轧控冷 针状铁素体 韧脆转变温度 析出物 

分 类 号：TG115.213[金属学及工艺—物理冶金]