Ion-irradiation effect on swelling and microstructure of BN particle dispersed liquid phase sintering SiC

• The swellings of each gradient, SiC, YAG (generated from Y 2 O 3 -Al 2 O 3 sintering additive) and BN after irradiation at 800 °C were calculated. Y 2 O 3 -Al 2 O 3 sintering additive and BN contributed 13.00 % and 31.39 % to the total swelling, respectively. • The microstructure evolution of LPS-SiC-BN after irradiation up to high fluence at 800 °C was explored. SiC, YAG and BN all stayed crystal, while the pure h-BN structure had been partially destroyed. • The microstructure evolution of YAG after irradiation changed from amorphization to point defect as irradiation varied from 300 °C to 800 °C result in a great decreasing on irradiation induced swelling. The boron nitride (BN) particle dispersed silicon carbide (SiC) materials were fabricated by liquid phase sintering (LPS) with Al 2 O 3 and Y 2 O 3 sintering additives as the reference matrix material for SiC composites. They were irradiated to 0.1/1/3/10 dpa by 5.1 MeV Si 2+ ions at 800 °C. Raman spectra indicated that the pure h-BN structure was partially destroyed following irradiation, while yttrium aluminum garnet (YAG) structure at grain boundaries formed from the sintering additives wasn't destroyed. TEM images and diffraction patterns indicated that the mechanism of microstructure evolution of SiC after irradiation up to high fluence at 800 °C was defect clusters induced by irradiation.