To study the corrosion behavior of NiCu-BN sealing coatings in marine environments and the effect of corrosion on coating properties,the NiAl bottom layer and NiCu-BN top layer were prepared on TC4 substrate by plasma spraying.The coatings were subjected to acidic salt spray corrosion and abradable tests.The phase and microstructure of the coatings were characterised by XRD and SEM.The results show that after 192 h acidic salt spray corrosion of NiCu-BN coating,corrosion dense zone with a thickness of about 100 μm is formed under the corrosion layer,and there are almost no holes inside the dense zone.The corrosion products on the surface of the corrosion layer are mainly micro-NaCuO2 and Cu64O.The average IDR value(Ratio of blade height change to total feed depth)of the coating in the spraying state is 9.76%±0.35%,while the average IDR value of the coating in the corrosive state is 13.01%±1.6%,which indicates that the acidic salt spray corrosion will reduce the wearability of the coating,The wear mechanism of the coating is changed from the plastic deformation wear to the mixed wear of the plastic deformation wear and the adhesive wear.
关键词
等离子喷涂/封严涂层/硬度/酸性盐雾/可磨耗性能
Key words
plasma spraying/sealing coatings/hardness/acid salt spray/wearability