Journal of the American Ceramic Society, Vol.89, No.6, 2051-2056, 2006
Fabrication of HAp-coated micro-channelled t-ZrO2 bodies by the multi-pass extrusion process
HAp-coated micro-channelled t-ZrO2 bodies were fabricated using a multi-pass extrusion process in which carbon powders were used to facilitate the formation of pores and ethylene vinyl acetate was used as a binder. The unidirectional pores and HAp coating layers can be obtained easily, using the extrusion process. The micro-channelled bodies were 180 mu m in diameter, and the HAp layer was uniformly coated on the pore walls. However, after being sintered above 1200 degrees C, the HAp decomposed and was transformed into beta-TCP, in which a large number of pores were observed. The maximum values of bending strength of HAp-coated and uncoated porous t-ZrO2 bodies sintered at 1500 degrees C were about 116 and 173 MPa, respectively, and their relative densities were about 57% and 63%, respectively.