抄録
α-Si3N4 ceramics with 5wt%Y2O3 and 3wt%MgO as sintering additives was sintered by using a Spark-Plasma-Sintering apparatus at 1773K for 0, 120, 300 seconds, at a heating rate of 1.7, 2.5,5 K/sec respectively. Some of the α-Si3N4 ceramics were further heated at the temperature range from 1773K to 2173K for 3600 seconds to regulate the micro structure of the ceramics. The micro hardness and the thermal conductivity of the ceramics were measured, and the micro structure of the ceramics were inspected by SEM, XRD and TEM, to study the relationship among the crystalline phase, the crystalline form and size, the crystallization of the grain boundary phase, the crystalline imperfection and the micro hardness, the thermal conductivity of the ceramics.
