Liquid impact erosion mechanism and theoretical impact stress analysis in TiN-coated steam turbine blade materials

Citation
Mk. Lee et al., Liquid impact erosion mechanism and theoretical impact stress analysis in TiN-coated steam turbine blade materials, MET MAT T A, 30(4), 1999, pp. 961-968
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science",Metallurgy
Journal title
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
ISSN journal
1073-5623 → ACNP
Volume
30
Issue
4
Year of publication
1999
Pages
961 - 968
Database
ISI
SICI code
1073-5623(199904)30:4<961:LIEMAT>2.0.ZU;2-J
Abstract
Coating of TiN film was done by reactive magnetron sputter ion plating to i mprove the liquid impact erosion resistance of steam turbine blade material s, 12Cr steel and Stellite 6B, for nuclear power plant application. TiN-coa ted blade materials were initially deformed with depressions due to plastic deformation of the ductile substrate. The increase in the curvature in the depressions induced stress concentration with increasing number of impacts , followed by circumferential fracture of the TiN coating due to the circul ar propagation of cracks. The liquid impact erosion resistance of the blade materials was greatly improved by TiN coating done with the optimum ion pl ating condition. Damage decreased with increasing TiN coating thickness. Ac cording to the theoretical analysis of stresses generated by liquid impact, TiN coating alleviated the impact stress of 12Cr steel and Stellite 6B due to stress attenuation and stress wave reactions such as reflection and tra nsmission at the coating-substrate interface.