Fabrication and Properties of AlN/CNT Composite Ceramics

Abstract

High thermal conductivity and dense AlN/CNT composite ceramics with additive Y2O3 were fabricated by spark plasma sintered (SPS) in this paper. The results indicated that CNT blocked the densification process in a certain extent, but in the sintering temperature of 1700°C, the relative density of composite ceramics were more than 97% with 1-10% volume fractions of CNT. The content of additive Y2O3 affected the thermal conductivity of AlN/CNT obviously. The thermal conductivity of composite material linearly decreased when the content of CNT increased and the tubular structure of CNT had been destructed during once sintering. The effects of the CNT structural damage to the thermal conductivity of composite ceramics were improved by adjusting the sintering process. The thermal conductivity of the composite ceramics with 3% volume fractions of CNT sintering in 1550°C/3min×3 was up to 145W/m•K, which higher than the single-phase AlN ceramics.

AlN/CNT Composites Ceramics by Spark Plasma Sintering

“…Thermal conductivity. Test results show that, materials thermal conductivity increased with the increase of CNT content in the system is monotonic decrease trend [6].The CNT has a very high thermal conductivity should strengthen the heat transfer performance of the system, for ceramic material, however, only a handful of system of the thermal conductivity is increased obviously [7]. Because, when the introduction of the second phase group, eventually thermal conductivity of system is not only affected by thermal conductivity and relative content, but also related to the distribution of two phase and microstructure features.…”