硅酸盐封孔剂对热喷涂304不锈钢涂层高温冲蚀磨损性能的影响  

Effect of Silicate Sealing Agent on High-Temperature Erosion Wear Properties of Thermal Spraying 304 Stainless Steel Coating

作　　者：张冲 汪建光 郑强 ZHANG Chong;WANG Jian-guang;ZHENG Qiang(Fujian Special Equipment Inspection and Research Institute,Fuzhou 350008,China)

机构地区：[1]福建省特种设备检验研究院,福建福州350008

出　　处：《材料保护》2022年第4期7-13,24,共8页Materials Protection

基　　金：福建省市场监督管理局科技计划项目(FJMS2020015);福建省质量技术监督局科技计划项目(FJQI2011056)资助。

摘　　要：采用热喷涂工艺制备的涂层常存在不少孔隙。为了弥补孔隙带来的抗腐蚀、冲蚀性能下降等问题,采用高速电弧在Q235钢基体上热喷涂304不锈钢涂层,采用封孔剂来处理热喷涂工艺带来的涂层孔隙,用碱金属硅酸盐基料、云母粉和SiO_(2)纳米颗粒为填料制备封孔剂,并用刷涂法对涂层进行封孔处理,研究了封孔层和喷涂层的抗高温冲蚀磨损性能。采用扫描电镜(SEM)和能谱仪(EDS)分别对喷涂层、封孔层的微观形貌和成分进行分析,研究喷涂层、封孔层在25,650℃温度下的冲蚀磨损性能和机理,并利用试验冲蚀磨损量估算了封孔层、喷涂层的冲蚀磨损寿命。结果显示:封孔层未见内部裂纹,与喷涂层结合紧密,但内部存在较多孔洞。封孔层在低攻角下的冲蚀磨损性能要好于未封孔的喷涂层。随着冲蚀温度由25℃升高至650℃,封孔层的冲蚀磨损量提高约20%,降低了封孔层的冲蚀磨损性能。封孔层、喷涂层的冲蚀磨损机理为低攻角下的犁沟、切削共同作用,以及高攻角下的挤压破坏。在冲蚀低攻角下,封孔层相比喷涂层具有更好的抗冲蚀磨损性能,在一定程度上封孔层能有效增强喷涂层的抗冲蚀磨损性能。The coating prepared by thermal spraying process often has many pores.In order to make up for the problems of corrosion resistance and erosion performance degradation caused by pores,304 stainless steel coating was prepared on the surface of Q235 steel by high-speed arc spraying,the pore sealing agent was used to treat the coating pores brought by the thermal spraying process.The pore sealing agent was prepared with alkali metal silicate base material,mica powder and SiO_(2) nanoparticles as fillers,and the coating was sealed by brush-coating method.The high-temperature erosion wear resistance of sealing layer and spraying coating was studied.SEM and EDS were used to analyze the micro morphology and composition of the sealing layer and spraying coating.The erosion wear performance and mechanism of the sealing layer and the spraying coating at 25℃and 650℃were studied.The erosion wear life of the sealing layer and spraying coating was estimated by the experimental erosion wear amount.Results showed that the sealing layer had no internal cracks and was tightly combined with the spraying coating,but there were many pores inside.The erosion wear performance of the sealing layer at low impact angle was better than that of the unsealed coating.As the erosion temperature increased from 25 to 650℃,the erosion wear amount of the sealing layer was improved by about 20%,and the erosion wear performance of the sealing layer decreased.The erosion wear mechanism of the sealing layer and spraying coating was the combined action of ploughing and cutting at low erosion impact angle,and crushing damage at high impact angle.At low impact angle,the sealing layer had better erosion wear resistance than the spraying coating.To a certain extent,the sealing layer could effectively enhance the erosion wear resistance of the spraying coating.

关 键 词：封孔剂 热喷涂 冲蚀磨损 高温 

分 类 号：TG147[一般工业技术—材料科学与工程]