부산대학교 도서관

Dense Si 2 BC 3 N ceramics were prepared through SPS sintering the amorphous Si 2 BC 3 N and Al 4 SiC 4 powders obtained from mechanical alloying. The phase compositions, microstructures, and mechanical properties, as well as the thermal shock resistance were investigated. In addition, evaluations of oxidation and the ablation resistance were also preceded. The results show that Al 4 SiC 4 phase can be detected at 1200 and 1400 °C under pressureless sintering. However, Al 4 SiC 4 can be decomposed to AlN and SiC phases under higher temperatures. As for the bulk Si 2 BC 3 N ceramics, the Al 4 SiC 4 additive induce the development of turbostratic BN(C) plates and improve the relative density consequently. Besides, the Al 4 SiC 4 plates are embedded in the matrix of ceramics. Therefore, the mechanical properties and thermal shock resistance are improved apparently with the addition of additive. Meanwhile, the additive containing composites have superior ablation resistance than the pristine Si 2 BC 3 N ceramics due to their higher relative density. [ABSTRACT FROM AUTHOR]