Sintering of calcium aluminate mixes

Abstract

Measurements of initial sintering shrinkage of mixes of CaAl₄O₇ and CaAl₂O₄ are reported in the temperature range 1360–1420°C. The particle size chosen was -45 μm and the mix proportions were 5 : 8, 4 : 10, and 3 : 11 by weight of CaAl₄O₇ and CaAl₂O₄ . The soaking periods were from 10 to 180 min. The time dependence of shrinkage showed that volume diffusion is the dominant mechanism in the sintering of mixes. At any temperature and sintering time, the shrinkage and densification increased with increase in CaAl₂O₄ content. The mixes produced a two phase system and the activation energy for the sintering was 251·6 kcal mol^-1.