Fabrication of porous alumina ceramics with uni-directionally-arranged continuous pores using a magnetic field

In order to fabricate porous ceramics with uni-directionrelly-arranged continuous pores, alumina compacts containing nickel wires as a pore forming agent were prepared by casting the alumina slurry on the plaster mold, on which nickel wires were settled and uni-directionally arranged with applying a magnetic field. Acid-leaching the nickel wires and subsequent sintering the samples resulted in the formation of continuous and straight pores in dense alumina matrix. Size of continuous pores could be varied with using nickel wires with different size. Interval between pores could! be controlled by coating the nickel wires with alumina prior to the arrangement in the magnetic field. Electrophoresis technique was useful to form a coated layer with controlled thickness.