回火温度对500MPa级海洋平台钢组织性能的影响  

Effect of tempering temperature on microstructure and properties of 500 MPa grade offshore platform steel

作　　者：周砚磊[1] 狄国标[2] 刘振宇[1] 王国栋[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 [2]首钢技术研究院,北京100041

出　　处：《材料热处理学报》2011年第10期106-111,共6页Transactions of Materials and Heat Treatment

基　　金：国家高技术研究发展计划(863计划)基金资助项目(2007AA03Z504)

摘　　要：对γ+α两相区淬火后的试验钢板进行300～600℃的回火处理,研究了回火温度对F500级海洋平台用钢组织及性能的影响。结果表明,400℃×1 h回火试样拉伸过程中出现屈服平台,并且回火温度越高不连续屈服现象越明显;回火中,马氏体板条束合并长大,部分位错发生静态回复,密度降低,多边形铁素体含量增加,基体上有大量20～40 nm富Nb的(Nb,Ti)C析出;500～550℃回火可以获得优良的强韧性能,达到F500级别海洋平台钢的要求。Effect of different tempering temperature on microstructure and properties of 500MPa grade offshore platform steel was studied.The plate samples were tempered from 300 ℃ to 600 ℃ for 1 h after quenching.The results show that yield point elongation appears during tensile test,and the phenomenon is more obvious by increasing of tempering temperature.With proceeding of tempering process,boundary of lath martensite packets becomes blurred and volume fraction of polygonal ferrite increases,static recovery of some dislocations also can be observed.Large quantity of Nb-rich（Nb,Ti）C carbides with diameter of 20 to 40 nm is precipitated in the process of tempering.Excellent performance can be obtained for the steel tempered at 500~550 ℃.

关 键 词：海洋平台用钢 回火温度 析出物 冲击韧性 

分 类 号：TG142.4[一般工业技术—材料科学与工程]