High-velocity impact behavior of co-continuous ceramic composite with different volume fractions

This article presents an experimental investigation on the dynamic behavior of a co-continuous ceramic composite (C4) produced by infiltrating Al5083 alloy into SiC foams. C4 has been defined as the designation used for the co-continuous ceramic composite fabricated via gas pressure infiltration of aluminum into the SiC foam skeleton, consistent with the terminology used in our earlier published works. The various SiC foams used for the infiltration such as 10, 20, and 30 pores per inch (PPI), were used as the reinforcing skeleton for infiltration. PPI has been defined as “Pores Per Inch,” the standard parameter denoting the pore/cell density of the SiC foam skeleton (10, 20, and 30PPI corresponding to coarse, medium, and fine pore structures, respectively). The behavior of the interpenetrating (C4) composites in dynamic regimes have been investigated through Split Hopkinson Pressure Bar (SHPB) and reported the stress-strain behavior of the composite at 1, 2, and 3 bar impact pressures. At 3 bar, the 30PPI-C4 sample exhibited peak stresses exceeding 33 MPa and strains approaching 30%. The specimens were subjected to high-velocity (∼800 m/s) impact by a spherical steel projectile using a gas gun impact system. The penetration process of the projectile into the (C4) composite and the associated energy absorption characteristics were analyzed. The results showed that 30PPI-C4 possessed the highest energy absorption capability (7.17 J/g). From the experiments it is observed that the 30PPI-C4 showed a 12% higher specific energy absorption when compared to 10PPI composite and 20PPI composite and which can be attributed to the refined cellular architecture, higher pore density, and improved load transfer capability of the 30PPI structure.