Fired hollow ceramic spheroids

摘要

A hollow, ceramic macrosphere or spheriod comprising a relatively smooth outer skin and cellular shell is produced in the 2-20 mm diameter range with specific gravities in the 0.2-1.2 range. The spheriods can be rendered inert to water and are stable at temperatures of 80 DEG to 1000 DEG C., depending on their composition. The porosity of the shell can be controlled through various additives and/or epoxy resin coating. The spheriods may be made from common clay and sodium silicate.