您目前所在的位置:首页 - 期刊简介 - 详细页面

铁道科学与工程学报

JOURNAL OF RAILWAY SCIENCE AND ENGINEERING

Vol. 10    No. 1    February 2000

[PDF Download]    [Flash Online]

    

Formation mechanism of laser-clad gradient thermal barrier coatings①
CHEN Guo-feng(陈国锋), FENG Zhong-chao(冯钟潮), LIANG Yong(梁 勇)

Institute of Metals Research, Chinese Academy of Sciences, Shenyang110015, P.R.China

Abstract:The stratified gradient thermal barrier coatings (TBCs) were obtained by laser cladding of ZrO2and NiCoCrAlY mixture powder. The coatings were four-layer structure: cellular dendritic ZrO2, dense ZrO2, Ni-based alloy bonding coating and substrate. The formation of the stratified TBCs was attributed to the insolubility of ZrO2in the Nibased alloy and the lower density of ZrO2than that of Ni-based alloy when both of them were in melted condition. The formation of two-layered ZrO2was related to the presence of Al in the Ni-based alloy, i) Al could be preoxidized into Al2O3that could be segregated in the grain boundaries of ZrO2during solidification process; ii) Al could be partially preoxidized into Al2O3, then Al and Al2O3could be segregated simultaneously at the grain boundaries of ZrO2during solidification process. Two formation processes were presented.

 

Key words: laser cladding; thermal barrier coatings; formation mechanismsDocument code: A

ISSN 1672-7029
CN 43-1423/U

主管:中华人民共和国教育部 主办:中南大学 中国铁道学会 承办:中南大学
湘ICP备09001153号 版权所有:《铁道科学与工程学报》编辑部
------------------------------------------------------------------------------------------
地 址:湖南省长沙市韶山南路22号 邮编:410075
电 话:0731-82655133,82656174   传真:0731-82655133   电子邮箱:jrse@mail.csu.edu.cn