摘要
本文对比了渗铝和铝－硅涂层的高温抗氧化性能，并用金相和电子探针分析技术研究了徐层的显微组织，从而揭示出硅抑制涂层“氧化缺口”破坏的机理在于：硅降低了铝的内扩散活性，使镍的外扩散活性相对提高，使合金最外表面形成很薄的表层，从而避免了ＭＣ碳化物的直接裸露；硅促进了ＭＣ→Ｍ＿６Ｃ的转化，生成富Ｓｉ的Ｍ＿６Ｃ，从而改善了涂层中碳化物自身的抗氧化性能。
he high temperature oxidation performances of the aluminized coating and aluminium-silicon coatinghas been examined.The microstructures of the coating are investigated by metallograph and electron probeanalysis techiques.It is revealed that the“Oxidation notch”is inhibited in Al-Si coating with the followingreasons: the internal-diffusion activity of aluminium is reduced by silicon,so that the external-diffusionactivity of nickel increased relatively,and a very thin layer is formed at the outside surface of alloy.Itavoids direct expose of MC carbide;the silicon has promoted MC→Si-rich M_6C transform and improved oxi-dation resistanc of carbide in coating.
出处
《材料工程》
EI
CAS
CSCD
北大核心
1994年第3期34-37,共4页
Journal of Materials Engineering
