Abstract
A simple surface treatment is found to improve mechanical strength of corundum crystals. The surface treatment is as follows: the titanium mono-oxide layer, 0.1 μm, thick is deposited onto the polished surface of the corundum crystals and the crystals are then fired at 1200 to 1300° C for a few hours in air. The treatment improves the mechanical strength of the corundum crystal surface. The surface microhardness increases by nearly × 2 and the mean wear resistance against the iron plate increases by several times. The surface hardening mechanism is discussed in relation to the diffusion of titanium ion into the corundum crystals.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R. P. Steijn, J. Appl. Phys. 32 (1961) 1951.
T. Nagai, K. Wasa and S. Hayakawa, J. Audio Eng. Soc. 22 (1974) 521.
Y. Oishi and W. D. Kingery, J. Chem. Phys. 33 (1960) 480.
J. B. Wachtman and L. H. Maxwell, J. Amer. Ceram. Soc. 40 (1957) 377.
C. R. Kennedy and R. C. Bradt, ibid 56 (1973) 608.
R. J. Bratton, J. Appl. Phys. 42 (1971) 211.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Nagai, T., Wasa, K. & Hayakawa, S. Surface hardening of ruby and sapphire. J Mater Sci 11, 1509–1512 (1976). https://doi.org/10.1007/BF00540885
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00540885