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Co-Continuous Ceramic Composites (C4) have been fabricated through gas pressure infiltration technique with SiC foam reinforcement of 10PPI and 20PPI, and with AA5083 alloy as matrix. The fabricated composites (C4) were tested for mechanical properties at static condition. This study delineates the effect of pores per inch (PPI) of SiC foams on the mechanical properties of the composite. The 10PPI C4 composite with highest content of AA5083 (81%) exhibited a compressive strength of 131 MPa, 5% greater than 20PPI C4 composite. The C4 composite displayed 65 times higher compressive strength than SiC foam (~2 MPa). The compression failure mode was found to be shear failure and vertical splitting, with the SiC foam failing first, followed by failure of AA5083. A positive correlation was observed between the compressive strength and hardness of the composite, where 10PPI composite exhibits 56 BHN, and 20PPI with 50 BHN. Additionally, microstructural analysis was performed to characterize the interface morphology of SiC foam and AA5083 alloy.

A novel approach of a gas pressure infiltration technique is presented for the synthesis of Co-Continuous Ceramic Composite (C4). SiC foams of varying pore sizes were infiltrated with aluminium AA5083. Optical examination revealed that the SiC foams contained open cells with a network of triangular voids. The number of pores-per-inch (PPI) in the foams was found to depend on the strut thickness and pore diameter. The compressive strengths of two foam configurations, 10 and 20 PPI, were estimated to lie between 1–2 MPa. After infiltration, the compressive yield strength of the resulting C4 was observed to increase to 126 MPa and 120 MPa, respectively, for the 10 and 20 PPI C4. Additionally, the infiltration of ceramic foam with the AA5083 alloy resulted in an increase in strength of 58–100 times when compared with plain ceramic foam. The failure modes of the composites in compression were analyzed by crack propagation and determining the type of failure. The study revealed that shear failure and vertical splitting were the predominant mechanisms of compression failure, and that the fabricated C4 is advantageous in mechanical properties compared to the plain ceramic foam. This study, therefore, suggests the use of C4 composites in armour applications.