摘要
用物理冶金常用的分析手段对不同取向的K403单晶和多晶材料渗态和高温长时热暴露条件下Al-Cr涂层的组织转变进行分析,研究应力对涂层组织的影响。结果表明,在900℃下,Al-Cr涂层组织稳定性极佳,可经受5000h热暴露。晶体取向对涂层的形成与转变无明显影响,但对σ相的排列与取向有明显作用。此外,应力加速了涂层的增厚和析出相的沉淀与粗化。在1050℃以上,涂层的β→γ转变在1000h内可完成,包括,σM6C相在内的析出相明显粗化,造成涂层组织严重损伤。
The microstructural transformations of Al-Cr coating on as-cast nickel base superalloy K403 with equiaxed grain or single crystal structure at high temperature for long term thermal exposure were analyzed by physical metallurgy methods.The effect of stress on degradation of coating was also investigated.The results indicate that the Al-Cr coating exhibits superior stability and can bear long term thermal exposure for 5000h bellow 900℃.The crystal orientation does not influence the formation or transformation of coating obviously,but can significantly vary the arrangement of σ phase.Stress promotes the thickness of coating,also the precipitation and coarsening of phases.Above 1050℃,the transformation of β→γ in coating completes for 1000h.Moreover,precipitates including σ phase and M6C carbide are coarsened very quickly and these cause the serious damage of coating structure.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2010年第12期55-60,共6页
Journal of Materials Engineering
