Fabrication and residual stresses of aluminum nitride ceramics sintered at high-pressure

摘要

High-density AlN ceramics were fabricated without sintering additives at high pressure (5.0 GPa)and temperature (1300 ～ 1800 ℃). The sintered bodies were characterized by XRD, SEM and miero-Raman spectroscopy (MRS). Controlling fracture mode was intragranular when the sintering temperature was as low as 1400 ℃ under 5.0 GPa. The values of residual stresses due to the distortion of the AlN lattice were assessed using the Micro-Raman Spectroscopy (MRS). The residual compression stress of the AIN ceramics sintered at 5.0 GPaand 1700 ℃ for 125 min is 2.0 GPa. The residual compression stress is increased according to the extension of the sintering time.