Nickel aluminate (NiAl2O4) powders were fabricated by a polymer solution route employing polyvinyl alcohol as a polymeric carrier in a mixed metal cation solution. The precursor gels were aerated and the calcined powders were also soft and porous. The crystalline development and microstructures of the synthesized powders were examined by X-ray diffractometry and scanning electron microscopy. The porous powders were ball-milled to sub-micron sized powders and their sintering behavior was examined. NiAl2O4 porous samples were fabricated with the ball-milled powders and their microstructures and compressive strengths were also examined. The ball-milled, fine NiAl2O4 powders were fully densified at a temperature of 1600 degrees C and the strength of the porous NiAl2O4 was found to be affected by the sizes of the starting powder and internal pores.

Keywords: nickel aluminate; porous body; polymer; ball milling; compressive strength