LIN Chengfu WEN Lishi QIAN Shengwei Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaKANG Datao Yanshan University
,
Qinhuangdao
,
China LIN Chengfu
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The morphology,microstructure,chemical composition and electrochemical behavior of the flame sprayed Zn-Al15 coating after corrosion test in sea water have been investigated.The results show that the selective dissolution of the laminar euteetic structure of the Zn-AI15 coating is the fundamental cause for its similarity in electrochemical behavior with Zn coating and kinetic behavior with Al coating.In the beginning period of sea water corrosion,the com- bined action of the laminar eutectic structure of the coating together with the residual stress may induce the stress corrosion cracking of the coating,and result in the crevice corrosion. The coating then will bulge and.fail in local areas due to embrittlement itself,stacking and ex- pansion of corroded products under the residual stress.
关键词:
flame sprayed coating
,
null
,
null
,
null
林成福
,
闻立时
,
钱声伟
,
康大韬
金属学报
本文研究了Zn-Al15涂层在海水腐蚀后的形貌、组织结构、化学成分及电化学特性。结果表明,Zn-Al15涂层片状共晶组织的选择性溶解是其电化学静特性与Zn涂层相似、动特性与Al涂层相似的根本原因。海水腐蚀初期,涂层的片状共晶组织与残余应力共同作用,引起涂层的应力腐蚀开裂,导致缝隙腐蚀。随后涂层的脆化、腐蚀产物的塞积、膨胀及残余应力等共同作用,使涂层鼓泡,导致涂层局部腐蚀失效。
关键词:
Zn-Al15涂层
,
failure analysis
,
corrosion
,
stress corrosion cracking
