Structural evolution in ZrC-SiC composite irradiated by 4 MeV Au ions

摘要

In-depth structural characterization has been performed to investigate the structural evolution in ZrC-SiC under irradiation by high dose of 4 MeV Au2+ions. XRD, SEM, TEM and Raman examinations have been utilized in the present study. The damage depth in SiC (∼1.55 μm) is found deeper than in ZrC (∼1.22 μm). SiC became amorphous under irradiation accompanied by volume expansion. ZrC kept crystalline but enhanced the formation of carbon vacancies and exhibited high density of dislocations whose structures varied with depth. Compressive stress due to swelling in amorphization of SiC result in 0.49% shrinkage of lattice parameters of ZrC unit cell. The grain boundaries kept structural integrity without occurrence of cracks or broadening, which implies absence of large degradation in mechanical properties of ZrC-SiC composite after irradiation.