Homogenous alumina tube with controlled pore morphology

Porous alumina tubes with homogenous microstructures were prepared from commercial alumina and polymethylmethacrylate (PMMA) powders with two kinds of particle sizes using a centrifugal molding technology. PMMA powders were used as the pore-forming agent and the proportion of fine to coarse particles was adjusted to control the pore morphology of the alumina tubes. The open porosity and air permeability was optimized with respect to the proportion of PMMA powders. The fracture strength decreased with increasing porosity and was insensitive to the proportion of fine to coarse PMMA powders despite the changing pore morphology. Analysis of the Weibull statistics showed that specimens with higher porosity exhibit a narrower scatter in fracture strength. A 50:50 mixture (v/v) of fine and coarse PMMA particles showed the lowest fluctuation in fracture strength. The present study paves the way to more reliable material design using porous materials. (c) 2005 Elsevier B.V. All rights reserved.