| Autor: |
Paseuth, Anongsack, Yamagata, Kazuo, Miura, Akira, Higuchi, Mikio, Tadanaga, Kiyoharu, Cinibulk, M. |
| Předmět: |
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| Zdroj: |
Journal of the American Ceramic Society; Jan2017, Vol. 100 Issue 1, p343-353, 9p |
| Abstrakt: |
Metastable c-Al xT1− xN is an important and well-established hard coating in the tool industry. To improve the mechanical and thermal properties, Al-rich c-Al xTi1− xN coatings with controllable preferred crystal orientations were fabricated via low-pressure chemical vapor deposition ( LP- CVD) in an industrial plant, using an AlCl3-TiCl4-NH3-Ar-H2 precursor system. The c-Al xTi1− xN coatings with (100)- and (111)-preferred orientations and average x values of 0.82 and 0.73, respectively, comprised c-Al(Ti)N/c-Ti(Al)N nanolamellae with average compositions of c-Al0.9Ti0.1N/c-Al0.6Ti0.4N and c-Al0.80Ti0.20N/c-Al0.50Ti0.50N; the average lamellar periods were 7.7 and 4.5 nm, respectively. High-resolution transmission electron microscopy indicated that the c-Al(Ti)N/c-Ti(Al)N nanolamellae were modulated along the <100> direction, implying coherent spinodal decomposition of c-Al xTi1− xN in the as-deposited state. The hardness of the c-Al xTi1− xN coatings varied from 33 to 36 GPa, depending on the (100)- or (111)-preferred orientation. Residual stress measurements in the as-deposited state showed tensile stress values of 1.8 and 4.6 GPa for the (100)- and (111)-oriented c-Al xT1− xN coatings, respectively. This stress may be generated by the difference in the thermal expansion coefficient of the c-Al xT1− xN coating and the carbide substrate and by coherency stress in the c-Al(Ti)N/c-Ti(Al)N nanolamellae. In situ high-temperature X-Ray diffraction results revealed high thermal stability up to 1000°C. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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