Materials Science Forum, Vol.486-487, 101-104, 2005
Fabrication of zirconia-hydroxyapatite composites for biological materials
Microstructure and mechanical behaviors of zirconia [ZR; ZrO2+3mol%Y2O3]-nano hydroxyapatite [HA; Ca-10(PO4)(6)(OH)(2)] nanocomposites were studied. A pulse electric current sintering (PECS) method was applied to fabricate ZR-HA composites as biomaterials. The reaction between zirconia and hydroxyapatite was successfully avoided. It was a successful preparation of bioactive composites in the quasi-binary system Ca-10(PO4)(6)(OH)(2) + ZrO2. One of the most serious problems is that when a mixture of zirconia and nano-hydroxyapatite powders was sintered, extensive chemical reaction between zirconia and hydroxyapatite was unavoidable. By applying a novel super-fast consolidation technique, pulse electric current sintering (PECS), the deleterious reactions were inhibited kinetically. The specimens contain 0, 10, 20, and 30wt% of hydroxyapatite on zirconia as remainder. Samples were sintered using the PECS method at 1100 degrees C, 1150 degrees C, 1200 degrees C, and 1250 degrees C, with increasing 100 degrees C/min, under a pressure of 50Mpa in vacuum atmosphere for 5min. Characterization of the samples was carried out using X-ray diffraction analysis at different sintering temperatures. Flexural strength was estimated with 3-point bending test. The relative density was acquired using an Archimedes method in toluene medium.