激光表面熔凝对超级13Cr不锈钢组织与性能的影响研究  

Effect of Laser Surface Melting on Microstructure and Performance of Super 13Cr Stainless Steel

作　　者：付安庆 赵密锋[2] 李成政 白艳 朱文军 马磊 熊茂县 谢俊峰[2] 雷晓维 吕乃欣 FU Anqing;ZHAO Mifeng;LI Chengzheng;BAI Yan;ZHUWenjun;MALei;XIONG Maoxian;XIE Junfeng;LEI Xiaowei;LV Naixin(State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials of CNPC Tubular Goods Research Institute,Xi'an 710077,China;Oil and Gas Engineering Research Institute,PetroChina Tarim Oilfield Company,Korla 841000,China;Oilfield Development Division,PetroChina Changqing Oilfield Company,Xi'an 710018,China;No.1 Gas Plant,PetroChina Changqing Oilfield Company,Yulin 718500,China;Bohai Equipment New Century Machinery Manufacturing Co.,Ltd.,Tianjin 300280,China;School of Science,Northwestern Polytechnical University,Xi'an 710072,China;School of Material Science and Engineering,Chang'an University,Xi'an 710064,China)

机构地区：[1]中国石油集团石油管工程技术研究院,石油管材及装备材料服役行为与结构安全国家重点实验室,西安710077 [2]中国石油塔里木油田公司油气工程研究院,库尔勒841000 [3]中国石油长庆油田公司开发事业部,西安710018 [4]中国石油长庆油田公司第一采气厂,榆林718500 [5]渤海装备(天津)新世纪机械制造有限公司,天津300280 [6]西北工业大学理学院,西安710072 [7]长安大学材料科学与工程学院,西安710064

出　　处：《中国腐蚀与防护学报》2019年第5期446-452,共7页Journal of Chinese Society For Corrosion and Protection

基　　金：国家科技重大专项(2016ZX05051);中石油重大科技专项(2018E-1809);陕西省创新人才推进计划-青年科技新星项目(2017KJXX-03)~~

摘　　要：研究了激光表面改性对超级13Cr不锈钢油管组织和耐蚀性能的影响。结果表明,采用200 W激光功率、5 mm/s扫描速率可在超级13Cr不锈钢表面获得厚度为200μm的熔凝层,熔凝层与不锈钢基体之间存在厚600μm的过渡层。激光熔凝层与过渡层均为马氏体组织,不锈钢基体为马氏体+奥氏体组织。熔凝层的硬度为410 HV,比基体硬度提高约25%;过渡层硬度为360~400 HV。与熔凝层和基体相比,过渡层的钝化区最宽、维钝电流密度最小且具有更高的点蚀电位和Kelvin电位。熔凝层的焊道界面处对局部腐蚀较为敏感。激光表面熔凝方法能显著提高超级13Cr不锈钢的表面硬度,超级13Cr耐腐蚀性能顺序为过渡层>基体>熔凝层,激光表面改性可在超级13Cr油管表面获得具有高耐蚀性的过渡层。Surface re-melted layer was obtained on super 13Cr stainless steel via laser surface melting(LSM)treatment,then,of which the microstructure,micro-hardness and corrosion performance were characterized by means of optical microscope,scanning electron microscope,X-ray diffractometer,microhardness tester,immersion test and scanning micro-zone electrochemical workstation.It is found that with a laser beam of 200 W and 5 mm/s of laser scanning speed,the LSM treatment could produce a remelting surface composed of 200μm thick LSM layer and a 600μm thick transition layer on the steel surface.The above two layers all show martensite microstructure,while the steel matrix is comprised of martensite and austenite.The micro-hardness of the LSM layer is 410 HV,which is 25%higher than the hardness of steel matrix,while that of the transition layer is 360~400 HV.Moreover,comparing with the LSM layer and steel matrix,the transition layer shows the widest passive range,lowest passive current density,and highest pitting potential and Kelvin potential.In addition,the inter-pass interface of the LSM layer is sensitive to localized corrosion.It is concluded that LSM treatment can significantly enhance the surface hardness of super 13Cr stainless steel,and the corrosion resistance of super 13Cr lies in the order of transition layer>steel matrix>LSM layer,indicating that a highly corrosion-resistant transition layer can be obtained on the steel surface via laser surface modification.

关 键 词：超级13Cr 不锈钢 激光熔凝 组织 硬度 腐蚀 

分 类 号：TG178[金属学及工艺—金属表面处理]