| Abstract: | It is very difficult to prepare full-densified aluminum nitride-boron nitride(AIN/BN) composite ceramics with homogeneous microstructure and high thermal conductivity.Spark plasma sintering (SPS)was used to fully densify the AlN/BN composites in this work.Microstructure,mechanical properties and thermal conductivity of the SPS sintered AIN/BN composites with 5-30 vol% BN were investigated.The results show that the microstructure of composites is fine and homogenous,and the AIN/BN composites exhibit high mechanical properties.To promote the growth of AlN grains and modify the distribution of grain boundary in AIN/BN composites,a heat treating methodology was introduced through gas pressure sintering(GPS).This processing was significantly beneficial to enhancing the thermal conductivity of the specimen.The thermal conductivity of AIN/BN composites with 5-30 vol% BN reached 60 W/m K after the samples were treated by GPS. |
