稀土Y对激光熔覆Inconel 625合金抗高温氧化和热腐蚀性能影响  

Effect of Rare Earth Y on High-temperature Oxidation and Hot Corrosion Resistance Performance of Inconel 625 Alloy Fabricated by Laser Cladding

作　　者：朱开阳 顾先锋 王晓玲 郭俊飞 李科 罗江凌 易江龙 ZHU Kaiyang;GU Xianfeng;WANG Xiaoling;GUO Junfei;LI Ke;LUO Jiangling;YI Jianglong(Guoneng Fuquan Power Generation Co.,Ltd.,Guizhou Fuquan 550501,China;Pourin Special Welding Technology Co.,Ltd.,Guangdong Jiangmen 529728,China;China-Ukraine Institute of Welding,Guangdong Academy of Sciences,Guangzhou 510650,China)

机构地区：[1]国能福泉发电有限公司,贵州福泉550501 [2]广东博盈特焊技术股份有限公司,广东江门529728 [3]广东省科学院中乌焊接研究所,广州510650

出　　处：《精密成形工程》2024年第6期153-163,共11页Journal of Netshape Forming Engineering

基　　金：广东省粤港澳大湾区国际科技创新中心建设(2022A0505050052);阳江人才振兴计划(RCZX2022018);江门市科技计划项目(2023780200040009603)。

摘　　要：目的分析稀土Y添加对激光熔覆Inconel 625组织和性能的影响规律,为严苛服役环境条件下的改性Inconel 625合金设计和制备提供借鉴。方法采用真空气雾化工艺,制备含有0.1%(质量分数)Y的IN625-Y粉末,并使用激光熔覆工艺分别制备了IN625和IN625-Y的熔覆试样。对比研究二者在组织和力学性能上的差异,分析稀土Y添加对激光熔覆IN625试样表面氧化膜组成、抗高温氧化、模拟烟气及熔盐热腐蚀性能变化趋势的影响。结果IN625合金和IN625-Y试样的显微组织主要由灰色富含Ni和Cr的γ-Ni基体相和枝晶组成,而IN625-Y试样晶粒组织更为细小,且有少量Laves相析出。IN625-Y和IN625试样的显微硬度分别为(268.8±3.1)HV0.3和(265.2±3.2)HV0.3,屈服强度、抗拉强度和延伸率分别从(430.1±20.8)、(753.2±19.1)MPa和(37.6±3.4)%,提升到(433.8±21.8)、(774.8±10.4)MPa和(39.2±1.1)%。激光熔覆IN625-Y试样的高温氧化增重和气氛熔盐条件下的热腐蚀增重速率均小于未添加稀土Y的IN625试样。结论基于稀土Y添加对IN625熔覆组织的晶粒细化和洁净化作用,添加稀土Y能整体提升IN625试样的力学性能。激光熔覆IN625-Y试样表面能形成致密且稳定的Cr_(2)O_(3)氧化膜,具有更强的抗高温氧化性能,能更好地抵御SO_(2)气体及NaCl/Na_(2)SO_(4)熔盐的热腐蚀。The work aims to analyze the influence of rare earth Y addition on the microstructure and properties of laser cladding Inconel 625,and provide guidance for the design and preparation of modified Inconel 625 alloy under harsh service environment conditions.In this research,vacuum atomization technology was used to prepare IN625 powder containing 0.1wt.%rare earth element Y,and laser cladding technology was also used to fabricate IN625 and IN625-Y cladding samples.By comparing and studying the differences in microstructure and mechanical properties of those cladding coatings,the influence of rare earth Y addition on the surface oxidation film composition,high temperature oxidation resistance,simulated flue gas and molten salt thermal corrosion resistance of IN625 samples were analyzed.The microstructure of the IN625 alloy and IN625-Y sample on the surface was mainly composed ofγ-Ni matrix phase and dendrite containing Ni and Cr.The IN625-Y sample had a finer grain structure and a small amount of Laves phase precipitation.The microhardness of IN625-Y and IN625 samples were(268.8±3.1)HV0.3 and(265.2±3.2)HV0.3,respectively.The yield strength,tensile strength,and elongation increased from(430.1±20.8),(753.2±19.1)MPa,and(37.6±3.4)%to(433.8±21.8),(774.8±10.4)MPa,and(39.2±1.1)%,respectively.The high-temperature oxidation weight gain and hot corrosion weight gain rate of the laser cladding IN625-Y sample under atmos-phere molten salt conditions were both lower than those of the IN625 sample without adding rare earth Y.Based on the grain re-finement and cleaning effect of rare earth Y addition on the IN625 cladding structure,the addition of rare earth Y can improve the overall mechanical properties of the IN625 sample.The surface of IN625-Y alloy with the addition of rare earth Y can form a dense and stable Cr_(2)O_(3)oxide film,which has stronger high-temperature oxidation resistance and better resistance to the hot corrosion of SO_(2)gas and NaCl/Na_(2)SO_(4)molten salt.

关 键 词：Inconel625镍基合金 激光熔覆 稀土元素钇 高温氧化 热腐蚀 

分 类 号：TG455[金属学及工艺—焊接]