Characterization of shock waves treated aluminum nitride powder and its potential for low-temperature sintering

AIN powder is treated by shock waves with pressure of 9.8 GPa. X-ray line b roadening effect is found as the result of strain stored in shocked AIN lat tice. This resultant average strain is estimated to be 2.85 x 10(-3). The r elated dislocation density in shocked AIN powder is calculated to be in the order of 10(11) cm(-2). The energy stored in shocked powder is estimated t o be 0.36 cal g(-1). The low temperature pressureless sintering process of shocked AIN powder with 6 wt.% additives is investigated. The obtained shoc ked sample sintered at 1610 degrees C for 4 h, has a density of 3.33 g cm(- 3), while unshocked sample has a poor value of 2.59 g cm(-3). This shows th at the dislocation in shocked AIN sample can promote the low-temperature si ntering. Furthermore, the recover behavior of strain is studied in this pap er. The changes of X-ray broadening in the shocked samples after being sint ered at different temperatures for different soaking times are examined. Th e results show that the strain recover effect is strengthened with the incr ease of sintering temperature and soaking time. (C) 2000 Elsevier Science S .A. All rights reserved.