表面纳米化处理对X80管线钢焊接接头的影响  

Influence of surface nano-crystallization on the welded joints of X80 pipeline steel

作　　者：王宇[1,2] 黄敏[2] 吕祥鸿[2] 高惠临[2] 

机构地区：[1]西安建筑科技大学材料科学与工程学院 [2]西安石油大学材料科学与工程学院

出　　处：《石油机械》2009年第1期17-20,25,共5页China Petroleum Machinery

摘　　要：采用表面机械研磨处理(SMAT)技术对X80管线钢焊接接头进行了表面自身纳米化处理。分析了SMAT前后X80管线钢焊接接头的疲劳及电化学腐蚀特性。结果表明,对X80管线钢焊接接头进行90min的SMAT后,可以在X80管线钢焊接接头表层一定深度范围以内获得纳米晶组织,纳米晶尺寸分布为5～15nm;在近似服役条件下的全应力范围内,SMAT可以显著延长X80管线钢焊接接头的疲劳寿命,其疲劳极限可提高13%;SMAT可提高X80管线钢焊接接头的电化学腐蚀性能,使其电化学腐蚀倾向和自腐蚀电流密度均有所降低。In this paper the welded joints of X80 pipeline steel are treated by surface mechanical attrition treatment(SMAT)technique,and the surface layer is characterized by means of OM,XRD and TEM.The changes of fatigue behavior and electrochemical corrosion behavior are examined under similar working condition of X80 pipeline steel before and after SMAT.The experimental results show that nanostructure surface layer with a certain thickness is formed in the welded joints after SMAT treatment for 90 min,which is composed of some random oriented uniform nanograins.Homogenization and continuum of microstructure of X80 pipeline steel welded joint are achieved.In addition,the fatigue and corrosion behavior can be improved by the SMAT process under high and low stress range in simulated service condition.The fatigue limit of SMAT X80 pipeline steel welded joint is increased by almost 13% than that of non-SMAT one,and the electrochemical tendency and self-corrosion current density are both decreased.

关 键 词：X80管线钢 焊接接头 表面机械研磨 疲劳寿命 电化学腐蚀 

分 类 号：TE973[石油与天然气工程—石油机械设备] TG142.31[一般工业技术—材料科学与工程]