Microstructure and polarisation behaviour of TiN–TiB2 matrix coating prepared by reactive plasma spraying
Source: Materials Science and Technology, Volume 26, Number 5, May 2010 , pp. 615-620(6)
Publisher: Maney Publishing
Abstract:Two TiN–TiB2 matrix coatings were prepared by reactive plasma spraying with two spraying powders (Ti+B4C+Cr, Ti+B4C). Their microstructure, phases, microhardness and polarisation behaviours in 3·5 wt-% NaCl solution have been investigated by SEM, XRD, hardness tester and electrochemical analyser. The thermodynamics analysis for reactive plasma spraying was discussed and the effect of addition of Cr on adiabatic temperature of TiB2 forming reaction was also analysed. The thermodynamics analysis shows that the reaction temperature during reactive spraying process is >2030 K. To satisfy the criterion of self-propagating high temperature TiB2 forming reaction, the addition of Cr should be >192·6 wt-% of the total weight of Ti and B4C. The experimental results show that the addition of Cr decreases the stress in the coating so as to the cracks of coating at the expense of microhardness, yet the microhardness of both two coatings is a high value. The corrosion resistance of TiN–TiB2 matrix coating was greatly improved. The anodic polarisation curve of TiN–TiB2 coating includes a narrow activation zone and a broad passivation zone, which indicates the stability of coating is very excellent. The addition of Cr increases the corrosion potential of coating, yet an overpassivation zone appears, which is due to the breakage of passivation film.
Document Type: Research Article
Affiliations: 1: School of Material, Hebei University of Science and Technology, Shijiazhuang 050018, China; State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China 2: State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China
Publication date: 2010-05-01
Authors wishing to cite fast track papers should give the journal name and the article DOI. This will enable reference linking via CrossRef and allow forward and backward citation tracking systems to associate the fast track citation with the final journal reference.Materials Science and Technology is the successor of two previous titles, for which digitised archives are available: Metal Science (Vols. 1—17; 1967—84) and Metals Technology (Vols. 1—11; 1974—84).
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Online submission site
- ingentaconnect is not responsible for the content or availability of external websites