Abstract
High density β-eucryptite ceramics was prepared using high purity and fine amorphous silica, α-alumina and lithium carbonate powders via the solid state reaction route.ß-eucryptite formation for the starting raw material
mixture goes to completion at 950°C. Accordingly, the mixture was calcined at 900°C , ground, compacted and conventionally sintered at 1090°C or flux-sintered at 1020°C. Their
relative densities reach 92 % and 99%, respectively. Their thermal expansion coefficients ( from RT. to 800°C) are 0.28×10-6 and 1.2×10-6, respectively. The dielectric constant of flux-sintered sample is 5.5 with loss tangent of 7.5×10-3. These properties are found suitable for substrate materials to micro-electronic applications.
