STRENGTHENING STRUCTURAL CLAY PRODUCTS BY INFILTRATING OF POROSITY WITH ALUMINUM

Traditional ceramics exhibit well known characteristics of hardness, c ompressive strength, and durability. Their weakness in tension relativ e to other materials and the deleterious effects of their pore phase s uggests that engineering improvements would result in wider applicatio n of this class of ceramic products. To this end, composites were fabr icated by infiltration of traditional ceramic preforms with molten alu minum using squeeze casting processes, and properties on small specime ns were evaluated to allow judgement of improvements due to the presen ce of the aluminum phase. The composites exhibited about two to four t imes the tensile strength of the unimpregnated ceramic preform. Punch shear strength tests aimed at determining the feasibility of fabricati ng thin composite sections (similar to 2-4 mm thickness) indicated sig nificant improvements in strength and toughness as did qualitative imp act tests. Composites produced by this squeeze casting method employin g traditional ceramic preforms could find application as wear resistan t materials and for exterior facing of structures.