Effect of Y2O3 addition on synthesis of AIN powder by carbothermal reduction-nitridation of Al2O3

The effect of Y2O3 on the synthesis of AlN by the carbothermal reduction-ni tridation of Al2O3 was investigated. The amount of Y2O3 addition was varied from 0 to 7.50 mass%, Nitridation was carried out at 1450 degreesC for 0-3 60 min in N-2 how. The grain sizes of synthesized powders were almost same regardless of the amount of Y2O3 addition. The synthesized AlN powders appe ared round shape. From XRD analysis, Y4Al2O9 was identified as an intermedi ate compound during nitridation. It was confirmed to be finally converted t o Y2O3 after nitridation. Therefore this synthesized powder is considered t o be advantageous to densification because the remaining Y2O3 acts as a sin tering aid.