Thermal Shock Behaviors of AlN/BN Laminated Ceramic Composites

Thermal Shock Behaviors of AlN/BN Laminated Ceramic Composites

AlN/BN laminated ceramic composites were fabricated by a flow casting method. The thermal shock behavior of both block AlN ceramics and AlN/BN laminated ceramic composites were carried out for comparison. To understanding the different of thermal shock resistance for the two materials, the microstructures were observed and the mechanical properties were tested. The results showed that, the thermal shock resistance of AlN/BN laminated ceramic composites was larger than that of block AlN ceramics. During the tests of residual strength after quenching from different temperatures, for the block AlN ceramics, the residual strength would decrease rapidly when the critical temperature difference ΔTc was larger than 450℃, on the other hand, for the AlN/BN laminated ceramic composites, the residual strength would decrease slowly and there was no obvious ΔTc.

AlN/BN laminated ceramic composites were fabricated by a flow casting method. The thermal shock behavior of both block AlN ceramics and AlN/BN laminated ceramic composites were carried out for comparison. To understanding the different of thermal shock resistance for the two materials, the microstructures were observed and the mechanical properties were tested. The results showed that, the thermal shock resistance of AlN/BN laminated ceramic composites was larger than that of block AlN ceramics. During the tests of residual strength after quenching from different temperatures, for the block AlN ceramics, the residual strength would decrease rapidly when the critical temperature difference ΔTc was larger than 450℃, on the other hand, for the AlN/BN laminated ceramic composites, the residual strength would decrease slowly and there was no obvious ΔTc.