Abstract:NiSi-BN abradable seal coating was prepared by atmospheric plasma spraying, and subjected to acid salt spray corrosion treatment for 192 hours. The microstructure, hardness, and bonding strength of the coating before and after corrosion were analyzed. The difference of abrasive scraping behavior between GH4169 blades and coating before and after corrosion at 650 ℃ was studied by high temperature ultra-high speed abrasive testing machine. The results indicate that the average hardness of the NiSi-BN coating after acid salt spray corrosion increases from (11.9±0.4) HBW to (18.2±1.7) HBW, and the average bonding strength remains unchanged at (6.7±1.5) MPa. The average IDR value of corroded NiSi-BN coatings increases from 10.77%±0.74% to 26.70%±4.60%. The abradability of the NiSi-BN coatings drops significantly after acid salt spray corrosion for 192 hours. This is mainly due to the high hardness of the corrosive areas on the top of coating. The hard corrosive areas of corroded coatings cause relatively higher wear height on the blades than the as-sprayed coatings during the abradable scraping process. The wear height of the blades increases from (0.05±0.01) mm before corrosion to (0.12±0.03) mm after corrosion, resulting in an increase in the IDR value of the corroded coating. The abradability of NiSi-BN coating after salt spray corrosion for 192 hours has deteriorated.