A colloidal method for manganese oxide addition to alumina powder and investigation of properties
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Various methods can be applied to introduce additives to ceramic materials. Of these methods, mechanical mixing may not always be suitable to obtain a uniform distribution of the small quantities of additive within the structure, requiring colloidal methods to be applied for the purpose. The addition of manganese oxide to alumina powder has been studied using a colloidal method. The effect of the manganese addition on alumina microstructure and the later stages of the densification behaviour was investigated, together with the hardness and mechanical strength. No evidence of secondary phase formation was detected between the manganese cation and alumina powder for up to 0.5wt% manganese addition, suggesting that manganese is in solid solution with alumina. The microstructural evidence presented suggests that small quantities of a manganese addition to alumina enhance the densification process through the formation of fast diffusion paths within the crystalline structure, similar to the effect of TiO2 addition.
KeywordsTiO2 Manganese Phase Formation Ceramic Material Secondary Phase
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- 1.S. Sumita, J. Ceram. Soc. Jpn Int. Ed. 99 (1991) 525.Google Scholar
- 2.E. Kostic, S. J. Kiss and S. Boskovic, Powder Metall. Inter. 22(2) (1990) 29.Google Scholar
- 6.A. H. Reides, in “Ullmann's Encyclopedia of Industrial Chemistry”, A16, 5th Edn, edited by E. B. Elvers, S. Hawkins and G. Schulz (VCH Verlagsgesellschaft, Weinheim, 1990) p. 131.Google Scholar
- 7.F. C. Jang and H. U. Anderson, “Ceramic Transactions-Ceramic Powder Science IV”, Vol 22, edited by S. Hirano, G. L. Messing and H. Hausner (American Ceramic Society, 1991) p. 209.Google Scholar
- 8.D. K. Shetty, A. R. Rosenfield, P. McGuire, G. K. Bansal and W. H. Duckworth, Ceram. Bull. 59 (1980) 1193.Google Scholar
- 9.Aicoa Chemicals Division Product Data, “AlCOA Aluminas in the Ceramics Industry”, Aluminium Company of America, 1501 Pittsburgh, PA 15219.Google Scholar
- 10.R. T. DeHoff, in “Applied Metallography”, edited by G. F. Vander Voort, (1986) p. 89.Google Scholar
- 11.H. Erkalfa, Z. Misirli, T. Baykara, F. Dogan and I. A. Aksay, in “Proceedings of the Third Euro-Ceramics”, Vol. 3, edited by P. Duran and J. F. Fernandez (Faenza Editrice Iberica, S. L., 1993) p. 549.Google Scholar
- 12.E. M. Levin, C. R. Robbins, H. F. McMurdie and M. K. Reser (eds), “Phase Diagrams for Ceramics” (American Ceramic Society, 1979) p. 114.Google Scholar
- 13.W. D. Kingery, H. K. Bowen and D. R. Uhlmann, “Introduction to Ceramics”, 2nd Edn (Wiley, 1976) p. 479.Google Scholar