化学镀镍对碳纤维增强聚酰亚胺表面WC/Co涂层抗热震性能的影响

在航空发动机涡轮叶片用碳纤维增强聚酰亚胺(C/PMR15)复合材料表面喷涂WC/Co涂层可以提高其抗氧化耐冲刷性能,采用整体热震法能够评定涂层与基体的结合力.研究了在C/PMR15基体上化学镀镍作为粘结底层对WC/Co喷涂层抗热震性能的影响,并与喷涂PMR15粉末作为过渡层的方法进行了比较.结果表明,在PMR15过渡层上不能得到完整的后续涂层,在化学镀镍粘结底层上可得到连续致密的镍基合金层和WC/Co涂层,镀镍层大幅度提高了基体抗氧化能力,缓和了WC/Co涂层和基体界面位置的热应力,涂层抗热震性提高.

Effects of Electroless Nickel Plating on Thermal Shock Resistance of WC/Co Coating on C/PMR15

Thermally sprayed WC/Co coating was introduced to increase the oxidation and erosion resistance of C/PMR15 composite material used for turbine vane of aeroengine. The adhesion of the coating to the substrate was evaluated using whole thermal shock method, while the effect of electroless nickel plating for C/PMR15 substrate on the thermal shock resistance of WC/Co thermally sprayed coating was studied and compared to PMR15 sprayed transition layer. Results showed that it was feasible to produce consecutive and compact nickel alloy coating and WC/Co coating using electroless nickel plating, while it was impossible to obtain those coatings if PMR15 transition layer was directly used. Moreover, the electroless nickel plating was able to efficiently relax the thermal stress at the interface of the WC/Co coating and the substrate, which accounted for the significantly increased oxidation resistance of the substrate and thermal shock resistance of the coating.