Effect of particle size distribution and calcium aluminate cement on the rheological behaviour of all-alumina refractory castables


Previous works based on statistical design of experiments (DoE) defined a model all-alumina self-now refractory castable (SFRC) with optimized particle size distribution for simultaneous high flowability index (FI) and superior post-sintering performance. This work compares the SFRC rheological behaviour and setting time with those of alternative all-alumina castables with different Andreasen aggregate particle size distribution modulus, and of the equivalent castables containing calcium aluminate cement. The model castable showed Bingham behaviour with low yield stress, viscosity and thixotropy, guaranteeing easier casting and less wear in the casting and/or projection equipment. However, as the coarse particle fraction increases, the castable flow tends to be non-linear and changes from Bingham to Herschel-Bulkley. The cement containing castables quickly loose flowability despite the applied shear. This work confirmed previous conclusions based on FI measurements and demonstrates the adequacy of the use of FI values in the calculation of FI response surface by DoE. (C) 2012 Elsevier B.V. All rights reserved.






Silva, AP; Segadaes, AM; Pinto, DG; Oliveira, LA; Devezas, TC

nossos autores


Funding from the Portuguese Foundation for Science and Technology (FCT, Project: PTDC/CTM/66302/2006) is gratefully acknowledged.

Partilhe este projeto

Publicações similares

Usamos cookies para atividades de marketing e para lhe oferecer uma melhor experiência de navegação. Ao clicar em “Aceitar Cookies” você concorda com nossa política de cookies. Leia sobre como usamos cookies clicando em "Política de Privacidade e Cookies".