为解决火电厂锅炉水冷壁热腐蚀问题.采用高速火焰喷涂技术首次制备出Fe—Al/SiC复合涂层,并对涂层的结合强度、显微硬度、抗热震性能和耐热腐蚀性能进行了研究。结果表明:Fe-Al/SiC复合涂层基体为Fe—Al相(Fe3Al、FeAl),SiC硬质相分布于涂层之中,与基体结合良好。整个涂层组织致密,呈现典型层状特征.具有较高的结合强度和显微硬度.孔隙率低。具有优异的抗热震性能和耐热腐蚀能力。经过150h涂盐热腐蚀后.Fe—M/SiC复合涂层的腐蚀增重只有20号钢的30%左右。涂层材料成本低廉.便于现场使用.应用前景广阔。
In order to solve the hot corrosion problem on the water-wall tubes in thermal power plants, HVFS technology was used to prepare the Fe-Al/SiC composite coating, and the bonding strength, micro hardness, thermal shock and hot corrosive resistance performance of the coating were studied. The results show that the matrix of Fe-Al/SiC composite coating is Fe-Al phase (Fe3Al ,FeAl) and the SiC hard phase is distributed all over the coating and is well bonded to the matrix. The whole coating is of compact structure with typical layered structure characteristic, high bonding strength, micro hardness, low void ratio, good thermal shock and hot corrosion resistance performance. The weight gain of Fe-Al/SiC composite coating after 150 h corrosion test was about 30% that of steel 20 under the same test condition. The cost of this coating material is comparatively less and it is convenient to put into use on site with wide application prospect.