摘要
用无机盐料浆法在K4104镍基高温合金表面制备了渗Al-Si涂层。改变粘结剂中铬酣(CrO3)的添加量得到了三种不同成分的Al-Si涂层。对三种Al-Si涂层进行1000℃×200h高温氧化性能试验,用扫描电镜(带能谱分析)对试样截面进行形貌观察及成分分析,并用Origin软件绘制氧化动力学曲线。研究结果表明,1000℃×200h氧化过程中三种Al-Si涂层均生成了连续致密的Al2O3氧化膜;涂层外层由不稳定的-βNiAl相(富Al)向稳定的-βNiAl相(富Ni)转变;三种Al-Si涂层均具有良好的抗高温氧化性;添加少量CrO3得到的Al-Si涂层内层形成了连续的富Si“隔层”,该“隔层”有利于阻碍合金元素与Al元素的互扩散,从而降低涂层中Al元素的退化速度。
Al-Si coatings were prepared on the superalloy K4104 by the slurry process. Three kinds of Al-Si coatings were obtained by changing content of CrO3 in the agglomerate. High temperature performance of the three Al-Si coatings was studied by static high temperature oxidation test at 1000°C for 200h. It is found that, Al-Si coatings formed in the process of oxidation test consist of continuous and compact Al2O3 oxide film, stable β-NiAl layer and Si rich layer. The three kinds of Al-Si coatings all exhibit excellent oxidation resistance due to the formation of Si rich layer, which hinders interdiffusion between Al in the coatings and elements of substrate alloy and reduces the speed of degradation of Al element in the coatings.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2007年第3期130-133,共4页
Transactions of Materials and Heat Treatment
