铝粉粒径对等离子熔覆铁基合金涂层耐腐蚀性的影响  

Effect of Aluminum Powder Size on the Corrosion Resistance of Plasma Cladded Iron-Based Alloy Coatings

作　　者：党国栋 刘继林 高培虎[1] 张世吾 闫志义 张丽娜 陈白阳 付瑞涛 李起保 金灿 范虎 DANG Guodong;LIU Jilin;GAO Peihu;ZHANG Shiwu;YAN Zhiyi;ZHANG Lina;CHEN Baiyang;FU Ruitao;LI Qibao;JIN Can;FAN Hu(School of Materials and Chemical Engineering,Xi’an Technological University,Xi’an 710021,China;Representative Office in Datong,PLA,Datong 037036,China;Shanxi Diesel Engine Industry Co.,Ltd.,Datong 037036,China)

机构地区：[1]西安工业大学材料与化工学院,陕西西安710021 [2]陆军驻大同代表室,山西大同037036 [3]山西柴油机工业有限责任公司,山西大同037036

出　　处：《材料保护》2023年第10期83-91,共9页Materials Protection

基　　金：国家自然科学基金项目(51771140);陕西省高校青年创新团队(金属腐蚀防护与表面工程技术,发动机关键部件材料研发及应用);陕西省重点研发计划项目(2019ZDLGY05-09);陕西省自然基金项目(2023-JC-YB-380);陕西省教育厅服务地方计划专项项目(19JC022)资助。

摘　　要：铝具有一定的化学活性,与氧发生反应后易形成致密的氧化膜,可有效阻碍样品的进一步深入氧化,起到很好的氧阻断保护作用,常用作阴极保护材料。在铁基合金涂层中引入铝可提高铁基合金涂层的耐蚀性,因此在等离子熔覆铁基涂层中加入不同粒径铝粉,研究其粒径大小对等离子熔覆铁基涂层组织形貌及耐蚀性的影响,分析其对熔覆层耐蚀性的影响机制。研究发现:铁基熔覆层与基体具有良好的冶金结合,熔覆层并未产生明显的裂纹及气孔。随着铝粉粒径(100~200,200~300,300~400,400~500目)的减小,熔覆层内部的黑色AlN相粒径也在减小,且分布更加均匀。熔覆层在3.5%NaCl溶液中均呈现出明显的钝化行为,自腐蚀电位分别为-0.665、-0.706、-0.752、-0.822 V,均高于基体的-0.883 V,自腐蚀电流密度分别为2.454×10^(-6)、6.313×10^(-6)、7.979×10^(-6)、9.710×10^(-6)A/cm^(2),均低于基体的3.323×10^(-5)A/cm^(2)。随着铝粉粒径的增大,熔覆层的耐蚀性逐渐增强,铝粉粒径在100~200目时所得到的熔覆层耐蚀性最好,且熔覆层耐蚀性均优于基体材料。Aluminum has a certain chemical activity,and easily forms a dense oxide film after the reaction with oxygen which can effectively prevent the sample from further deep oxidation,playing good oxygen-blocking protection,commonly used as cathodic protection material.By introducing aluminum into iron-based alloy coatings,the corrosion resistance of these coatings can be enhanced.In this research,different particle sizes of aluminum powder were incorporated into plasma cladded iron-based coatings to investigate the influence of particle size on the microstructure,morphology and corrosion resistance of the coatings.The underlying mechanisms affecting the corrosion resistance of the clad layers were also analyzed.Results showed that the iron-based clad layer had good metallurgical bonding with the substrate and the clad layer did not produce obvious cracks and pores.As the particle size of the aluminum powder(100~200 mesh,200~300 mesh,300~400 mesh,400~500 mesh)decreased,the size of the black AlN phase within the overlay also reduced,resulting in a more uniform distribution.All overlays displayed pronounced passivation behavior in a 3.5% NaCl solution.The self-corrosion potentials were -0.665,-0.706,-0.752 and -0.822 V,which were higher than that of the substrate(-0.883 V),and the self-corrosion current densities were 2.454×10^(-6),6.313×10^(-6),7.979×10^(-6) and 9.710×10^(-6) A/cm^(2),which were lower than that of the substrate 3.323×10^(-5) A/cm^(2).As the particle size of aluminum powder in-creased,the corrosion resistance of the clad layer gradually increased,and the best corrosion resistance of the clad layer was obtained when the particle size of aluminum powder was 100~200 mesh,and the corrosion resistance of the clad layer was better than the base material.

关 键 词：等离子熔覆 蠕墨铸铁 铁基合金涂层 铝粉粒径 微观组织 电化学性能 

分 类 号：TG174.442[金属学及工艺—金属表面处理]