Characterization of a New Sintered Calcium Aluminate Cement
1 Mineração Curimbaba LTDA, Poços de Caldas, MG, 37701-970/Brazil
2 Elfusa Geral de Eletrofusão LTDA, São João da Boa Vista, SP, 13872-900/Brazil
3 Faculdade Pitágoras, Poços de Caldas, MG, 37702-386/Brazil
Revision
Volume 9, Issue 3, Pages 67 - 70
Abstract
Traditionally, calcium aluminate cements (CACs) are produced by fusion or sintering using precursor sources of high alumina and limestone with acceptable grades of impurities. The main impurities are silica, ferrites, magnesia, titania and alkalis. Due to the production conditions and raw materials compositions, CACs can be obtained with different proportions in the crystalline phases, being the main ones CA, CA2 and C12A7, where CA is generally the major phase, being primarily responsible for the compressive strength of the CACs. As the fusion processing costs are considerably high, it’s presented the characterization of an intermediate-purity CAC produced by sintering of a bauxite and lime mixture in a rotary kiln resulting in a cement with suitable workability and setting time, in addition to good refractoriness and mechanical resistance. It was obtained CA as major phase with quantification performed by the Rietveld method (XRD/RM).
Keywords
calcium aluminate cement, sintering, bauxite, lime
References
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