Structure and fracture behavior of ion-beam-modified SiC-Al2O3-ZrO2 ceramic composites

SiC-Al2O3-ZrO2 ceramic composite with heterointerfaces was prepared by hot pressing and irradiated with 1.2 MeV Si ions at room temperatures. The microstructural evolution and mechanical properties were investigated. The results showed that the phase transformation of zirconia revealed by GIXRD and TEM are associated with the accumulation of oxygen vacancies clusters originated by damage and the size of displacement cascades. Complete amorphization of SiC particles were observed at 5.5 dpa, and developed into collection band at 55 dpa due to the mixture of point defect clusters and extend defects at high damage level. The nanohardness and elastic modulus irradiation decreased with increasing of damage level. The fracture behavior of materials and relative mechanism under ion irradiation were discussed.