A novel approach to high-strength,translucent whitewares using prefired materials

Abstract

A novel high strength, translucent whiteware for use in high quality hotels and restaurants has been made using two prefired materials, each having the same composition but with different median particle sizes, and only a small amount of clay to minimise the firing shrinkage and its anisotropy. This paper deals with the determination of the characteristic properties of the novel whiteware. The densification heat treatment has been established to be the same as that used for hard porcelain i.e. greater than or equal to1350degreesC. The phases found in the fired body are anorthite as the major phase and mullite and glass as minor phases. The glass phase allows the body to be densified and, with a high volume fraction of anorthite, yields a translucent material. The mullite crystals act as creep inhibitors. Flexural strength measurement studies using slip-cast test pieces have yielded strength values in excess of 130 MPa. The use of a low clay content has an adverse effect on the green strength (similar to0.7 MPa). However, this drawback was overcome by using acrylic binders, such as Duramax B-1007 about 4% of which produces approximately 2.5 MPa green strength value.