RELIABILITY OF ALUMINA CERAMICS .2. EFFECT OF PROCESSING

In this paper an attempt is made to review the mechanical properties t hat can currently be achieved with the best alumina powders available by utilizing a series of simple processing strategies and surface prep aration techniques. The processing techniques include cold-isostatic p ressing, slip casting, settling and centrifuging as well as hot-isosta tic pressing of as-sintered alumina samples. The surface preparation t echniques include grinding and polishing as well as annealing and grin ding in the green state. While the fracture strength can be increased from 460 MPa for cold-isostatic pressing to 925 MPa for a centrifuged and cast alumina slip, the Weibull modulus remained between 8 and 12 f or most processing strategies. (C) 1997 Elsevier Science Limited. All rights reserved.