Fabrication of Zirconia-Nickel Functionally Gradient Materials by Slip Casting and Pressureless-Sintering

A powder processing technique has been developed for the fabrication of tetragonal zirconia-nickel functionally gradient materials using slip casting and pressureless-sintering. Rheological behavior of slips was studied. Single-layer zirconia-nickel green compacts with various zirconia/nickel volume ratios were characterized by permeability and pore radius. A multilayer zirconia-nickel green compacts with a stepwise compositional gradient was formed and sintered in argon atmosphere. One of the keys to successful fabrication was to minimize differences in permeability and pore radius between neighbouring layers in a multilayer green compact to avoid fracture during drying in an ambient atmosphere.