摘要
采用火焰喷涂技术在E335钢上制备粉末状Fe基涂层。研究了后续热处理对涂层组织和力学性能的影响。在623 K、823 K和1023 K的空气中对涂层进行后续热处理1 h,然后随炉在空气中冷却。结果表明,随着退火温度的升高,823 K和1023 K处理后涂层的微观结构发生了如下变化:孔隙率降低,碳化物和氧化物形成。在623 K时,涂层的主要相为固溶体FCC(Fe,Ni)、金属间化合物AlFe_3和碳化物[Fe,C];碳化铁、碳化钼和氧化铁Fe_3O_4作为主要相增强了823 K退火涂层中的固溶体FCC(Fe,Ni)相;但在1023 K处理涂层中观察到碳化钼和氧化物Fe_3O_4消失了。823 K退火涂层的耐磨性优于623 K和1023 K退火涂层,其磨损率最低。
The Fe-based coatings in powder form were deposited on a steel type E335 by flame spraying technique.The effects of the post heat treatment on the microstructure and the mechanical properties of sprayed coatings were studied.Post heat treatment was conducted in a furnace in air at 623 K,823 K and 1023 K for 1 h and then cooled in air.The results showed that with the increase of annealing temperature,the microstructure of coating treated at 823 K and 1023 K had several changes as follows:the reduction of porosity,formation of carbides and oxides.It was found that the solid solution FCC(Fe,Ni),intermetallic compound AlFe3 and carbides[Fe,C]were the main phases for coatings as-sprayed and treated at 623 K and while iron carbide,molybdenum carbide and oxide as Fe3O4 became the main phases and reinforced the solid solution FCC(Fe,Ni)phase for annealed coatings at 823 K.However,it was observed the disappearance of molybdenum carbide and oxide Fe3O4 at 1023 K.The coating annealed at 823 K exhibited an excellent wear resistance than the as-sprayed and annealed coatings at 623 K and 1023 K and shows the lower wear rate than another coating treated or as sprayed.
关键词
热喷涂
涂层
后续热处理
显微组织
磨损
thermal spray
coatings
post heat treatment
microstructure
wear