激光熔覆C276合金涂层及其耐熔盐腐蚀性能研究  

Study on the Laser-Cladding C276 Alloy Coating and Its Corrosion Behavior in Molten Salt

作　　者：边兰 张帆 杨德林 贾升 宋哲远 王茜 张亮 张峻巍[1] Bian Lan;Zhang Fan;Yang delin;Jia Sheng;Song Zheyuan;Wang Qian;Zhang Liang;Zhang Junwei(School of Materials and Metallurgy,University of Science and Technology,Anshan Liaoning 114051,China;Products and Techniques Managment Department,Baosteel Zhanjiang Iron&Steel Co.,Ltd,Zhanjiang Guangdong 524072,China;School of Science,University of Science and Technology,Anshan,Liaoning 114051,China;Fushun Longye Chemical Co.,Ltd,Fushun,Liaoning 113217,China)

机构地区：[1]辽宁科技大学材料与冶金学院,辽宁鞍山114051 [2]宝钢湛江钢铁有限公司制造管理部,广东湛江524072 [3]辽宁科技大学理学院,辽宁鞍山114051 [4]抚顺隆烨化工有限公司,辽宁抚顺113217

出　　处：《应用激光》2022年第12期27-37,共11页Applied Laser

基　　金：国家自然科学基金(51874091、5210010681)。

摘　　要：核电安全已成为当前核电发展的主要问题,核电结构材料因腐蚀造成的失效是导致安全问题的主要原因之一。为提高熔盐堆候选材料304不锈钢的耐蚀性,采用激光熔覆技术在304不锈钢表面熔覆Hastelloy C276涂层及添加1.0%(质量分数)Y_(2)O_(3)的C276涂层,并研究了两种涂层的组织、物相、硬度及其耐FLiNaK熔盐腐蚀性。结果表明,两种熔覆层与基体结合良好。C276熔覆层显微组织从上到下依次由等轴晶、二次树枝晶、胞状晶、柱状晶和平面晶组成,平均硬度为297 HV。添加Y元素后熔覆层组织类型无明显变化,熔覆层硬度略有下降。在700℃、FLiNaK熔盐中静态腐蚀20 h后,304不锈钢表现为明显的晶间腐蚀和Cr元素流失,腐蚀层深度为30μm;而C276与添加稀土的熔覆层表面有腐蚀坑出现,纯C276熔覆层腐蚀深度为16μm,添加Y元素后,腐蚀层深度为8μm左右,耐熔盐腐蚀性相较基体304有很大的提升。The safety of the nuclear power has become the main problem in the development,and the failure of structural materials caused by corrosion is one of the main reasons for the safety problems.In order to improve the corrosion resistance of 304 stainless steel,which is a candidate material for molten salt reactor,Hastelloy C276 coating and C276 coating with 1.0%(mass fraction)Y_(2)O_(3)were cladded on the surface of 304 stainless steel by laser cladding technology.The microstructure,phase composition,hardness and resistance to FLiNaK molten salt were studied,respectively.Results show that the two cladding layers are well combined with the substrate.The microstructure of C276 cladding layer is composed of equiaxial,secondary dendrite,cellular,columnar and planar grains from top to bottom,and the average hardness is 297 HV.After Y element was added,the microstructure of the cladding layer does not change obviously,and the hardness of the cladding layer decreases slightly.After static corrosion at 700℃for 20 h in FLiNaK molten salt,304 stainless steel exhibits obvious intergranular corrosion and Cr element loss and the corrosion depth is 30μm.The corrosion depth of C276 cladding layer is 16μm and the corrosion depth is about 8μm after Y addition.The corrosion resistance of the laser cladding C276 coating in the molten salt is greatly improved compared with that of the 304 substrate.

关 键 词：激光熔覆 C276合金 氧化钇 熔盐腐蚀 

分 类 号：TG174[金属学及工艺—金属表面处理]