溅射AlY涂层对Ni基合金抗热腐蚀性能的影响  

Effect of Sputtered AlY Coating on Hot Corrosion Resistance of Ni-base Superalloy

作　　者：付广艳[1] 王子龙[1] 刘群[1] 张小玲[1] 祁泽艳[1] 

机构地区：[1]沈阳化工大学机械工程学院,辽宁沈阳110142

出　　处：《稀土》2017年第4期88-94,共7页Chinese Rare Earths

基　　金：辽宁省“百千万人才工程”项目(2012921045)

摘　　要：采用磁控溅射方法在镍基合金表面制备AlY涂层,并对涂层试样分别进行预氧化和真空扩散退火处理,对比研究镍基合金、预氧化AlY涂层试样和真空扩散退火AlY涂层试样在900℃硫酸盐膜下的热腐蚀动力学及腐蚀产物的组成。结果表明,各试样的腐蚀动力学均分段遵循抛物线规律。对于24 h的腐蚀增重,涂层试样明显小于镍基合金,预氧化试样略低于真空扩散退火试样。镍基合金腐蚀膜分层且开裂,外层主要是Cr_2O_3及NiO的混合物,其下有不连续的Al_2O_3;真空扩散退火试样的腐蚀膜外层是连续的Al_2O_3,其下是Cr和Ni的氧化物,再下是连续的Y_2O_3;预氧化试样形成了与真空扩散退火试样相似的腐蚀膜,但略薄于真空扩散退火Al Y涂层试样。表面连续Al_2O_3膜及连续的Y_2O_3层的形成,提高了腐蚀膜的保护性和粘附性,不同方法处理的AlY涂层提高了镍基合金的抗热腐蚀性能。A1Y coating on Ni-based superalloy was prepared by magnetron sputtering method. The specimens were treated with pre-oxidation （PO） or vacuum diffusion annealing （VA）. The hot corrosion behavior of the Ni-base superalloy and A1Y coating specimens beneath the deposits of Na2SO4 at 900 ~C was investigated. The results show that the corrosion kinetics of all specimens follow parabolic law at different times. The corrosion weight gain of the A1Y coating specimens is much smaller than that of Ni-based superalloy, and the PO specimen has slightly lower weight gain than the VA specimen after 24 hours corro- sion. The corrosion film on Ni-based superalloy is a delaminated and cracked mixture, including Cr2O3, NiO outer layer and non-continuous Al2O3 inner layer. The corrosion film on the VA specimen is a continuous Al2O3 outer layer and the oxides containing Cr and Ni, as well as a continuous Y203 inner layer. The PO specimen has a similar and thin corrosion film with VA specimen. The continuous Al2O3 and Y2O3 film on the A1Y coating specimens enhance protective effect and cohesive force of the corrosion product. The A1Y coating after PO or VA treatment improves hot corrosion resistance of the Ni-base superalloy.

关 键 词：磁控溅射 AlY涂层 真空扩散 预氧化 热腐蚀 

分 类 号：TG174.4[金属学及工艺—金属表面处理]