真空预氧化对冷喷涂CoNiCrAIY涂层组织及热腐蚀性能的影响

利用冷喷涂技术制备CoNiCrAlY涂层，并对涂层进行真空预氧化处理。结合x射线衍射，扫描电镜，能谱分析和透射电镜等方法分析了CoNiCrAlY涂层真空预氧化前后的微观组织结构，并研究了喷涂态涂层和真空预氧化涂层在900℃的75％NazSOt＋25％NaCl（质量分数，下同）熔盐中的热腐蚀行为和机理。结果表明：冷喷涂CoNiCrAlY涂层呈纳米晶结构，含氧量为0．12％，孔隙率小于0．28％（体积分数）。真空预氧化处理改善了涂层粒子间的结合，使涂层更加致密，并在涂层表面生成厚约0．26／zm连续、致密的a—Al202氧化膜；喷涂态涂层和真空预氧化涂层在热腐蚀150h后表面均生成了以a—AlzO...

Full description

Saved in:
Bibliographic Details
Published in材料工程 no. 4; pp. 12 - 16
Main Author 张林伟 王鲁 王全胜 宁先进
Format Journal Article
LanguageChinese
Published 2013
Subjects
MCrAlY涂层
冷喷涂
热腐蚀
真空预氧化
纳米晶
Online AccessGet full text

Cover

More Information
Summary:利用冷喷涂技术制备CoNiCrAlY涂层，并对涂层进行真空预氧化处理。结合x射线衍射，扫描电镜，能谱分析和透射电镜等方法分析了CoNiCrAlY涂层真空预氧化前后的微观组织结构，并研究了喷涂态涂层和真空预氧化涂层在900℃的75％NazSOt＋25％NaCl（质量分数，下同）熔盐中的热腐蚀行为和机理。结果表明：冷喷涂CoNiCrAlY涂层呈纳米晶结构，含氧量为0．12％，孔隙率小于0．28％（体积分数）。真空预氧化处理改善了涂层粒子间的结合，使涂层更加致密，并在涂层表面生成厚约0．26／zm连续、致密的a—Al202氧化膜；喷涂态涂层和真空预氧化涂层在热腐蚀150h后表面均生成了以a—AlzOa为主的致密连续氧化膜，保护了基体免受腐蚀破坏；真空预氧化处理有效减缓了S和Cl等元素向涂层内扩散的速率，使涂层的抗腐蚀性能提高了近一倍。
Bibliography:11-1800/TB
ZHANG Lin-wei, WANG Lu, WANG Quan-sheng,NING Xian-jin （School of Materials Science and Engineering,Beijing Institute of Technology, Beijing 100081, China）
MCrA1Y coating nanocrystalline hot corrosion ; cold spray vacuum pre-oxidation
CoNiCrA1Y coatings were prepared by cold spray process. After deposition, the pre-oxida- tion of the coating was performed by vacuum heat-treatment. The microstructure and phase constitu- ent of coating were characterized by XRD, FE-SEM and TEM. The corrosion behavior and mecha- nisms of as-sprayed and pre-oxidized coatings in molten 75%NazSO4 ＋25%NAC1 （mass fraction, the same below） at 900＂C were also studied. The results show that the as-sprayed coating presents a nanocrystalline structure with low porosity （less than 0.28% volume fraction） and low oxygen con- tent （0.12%）. Vacuum pre-oxidation treatment improves the bonding status of particle interface and forms a continuous, uniform and dense a-Al2O3 layer, with an average thickness of 0.26/xm. As- sprayed and pre-oxi
ISSN:1001-4381
1001-4381