水轮机抗汽蚀合金涂层性能评价

Evaluation of Properties of Anti-Cavitation Alloy Coatings on Hydraulic Turbine

采用超音速火焰喷涂技术在水轮机叶片表面制备了Deloro60、Stellite6、Stellite21、Sus316L、JK135五种合金涂层,分析了各合金涂层的涂覆质量、组织成分和抗汽蚀性能。结果表明:用超音速火焰喷涂技术制备的合金涂层涂覆均匀,与基体附着良好,合金涂层中弥散分布的强硬碳化物相提高了合金涂层的抗汽蚀能力;Deloro60合金涂层表面硬度高于其余4种合金涂层的,达到621 HV,在实际工况条件下经过3 850h运行后其质量损失率为1.6%,面积脱落率为0.26%,低于其余4种合金涂层的,Deloro60合金涂层在汽蚀环境中具有较好的综合性能。

Alloy coatings of Deloro60,Stellite6,Stellite21,Sus316 Land JK135 were prepared on the blade surface of hydraulic turbine by supersonic flame spraying technology.The coating quality, microstructure,chemical composition and cavitation resistance of the alloy coatings were analyzed.The results show that the alloy coatings prepared by supersonic flame spraying technology were uniformly coated and adhered well to base metal.The dispersive carbides with high hardness and strength in the alloy coatings improved the cavitation resistance of the alloy coatings.The Deloro60 alloy coating had a surface hardness of 621 HV,higher than that of other alloy coatings.When the Deloro60 alloy coating worked in real work condition for 3 850 h,the weight loss ratio was 1.6% and area loss ratio was 0.26%,higher than those of other four kinds of alloy coatings.The Deloro60 alloy coating had good comprehensive properties in cavitation condition.