Elastic properties of spark plasma sintered (SPSed) ZrB2–ZrC–SiC composites

This study investigates the elastic moduli of ZrB2–ZrC–SiC (ZZS) composites with or without AlN and Si3N4 additives consolidated by spark plasma sintering. The effect of the additives on the properties is assessed. The soundwave velocities in the longitudinal and transverse modes were measured. The elastic moduli were calculated from the sound velocities and densities. The results indicate that the elastic moduli of ZrB2–ZrC–SiC materials depend on additives and porosity. This dependence is described by a linear relation between the elastic moduli and the longitudinal soundwave velocity. The obtained elastic moduli of the fully dense ZrB2–ZrC–SiC materials with AlN and Si3N4 additives are the following: E = 459 GPa, G = 196 GPa, ν = 0.17 for ZZS, E = 418 GPa, G = 178 GPa, ν = 0.18 for ZZS + AlN, and E = 462 GPa, G = 197 GPa, ν = 0.17 for ZZS + Si3N4.