Wp. Tai et al., Processing of lightweight, high-strength porcelains using an alumina cement to replace feldspars and clays, J AM CERAM, 83(7), 2000, pp. 1658-1662
New lightweight, high-strength porcelain bodies, using only nonplastic raw
materials such as glass microspheres, quartz, and alumina cement, were fabr
icated and the effect of quartz particle size was investigated. Decreases i
n the green strength, relative to an increasing content of glass microspher
es, were attributed to the decrease in the density and the relative decreas
e in the volume of alumina cement. The phases in the fired body mere glass,
alpha-quartz, cristobalite, anorthite, and a small amount of alpha-alumina
. The large quartz particles (10-32 mu m in size) could not be densified to
closed porosity, because of underfiring, whereas smaller quartz particles
(4-10 mu m in size) permitted densification to closed porosity at 1300 degr
ees C. The high flexural strength when using medium-sized quartz particles
(6-20 mu m, content of 30 wt%) was attributed to a stronger prestress and h
igher density that was due to better vitrification.