Papers by Keyword: Calcium Zirconium Phosphate

Abstract: A long-term stable material, which has two main crystalline phases – fluorapatite (FA) and calcium zirconium phosphate (CZP) [1, 2] and could be processed to dense sintered samples was tested related to the use with two application forms – spongiosa-like specimen and foils. The suitability of various sintering additives was investigated alone and in diverse combinations. During sintering of the spongiosa-like samples volume shrinkage of about 50% was observed whereas the shrinkage in x,y plane was about twice of the shrinkage in z direction. The cuboid form was not affected by the shrinkage. The compression strength of the spongiosa-like materials was in the range of 1MPa up to 1.6MPa. A ceramic foil was generated via foil slip casting of a slip containing about 38vol% of FA-CZP. Temperature programs were created for debindering and sintering of the green foil and the four-fold laminate, respectively.

Abstract: The influence of several sinter additives (three glasses, magnesium acetate, bismuth trioxide) on the compressive strength and also on the solubility of a sintered ceramics, which is composed of 57.6Mol% CaO, 26.2Mol% P2O5, 10.4Mol% ZrO2 and 5.8Mol% CaF2 was tested. The amount of sinter additives, pre-mixing of the powders, pressure power, sintering temperature and sintering time were varied. The most dense samples were produced with the finest powders (D50 ~ 1/m) and the highest sintering temperatures (1200°C). The mechanical stability of the samples was more influenced by the particle size of the powders than by the kind of binder as well as the pressure power. The compressive strength of the sintered samples ranged between 180MPa (D50 of the powder = 2.4/m) and 530MPa (D50 of the powder < 1/m). Storing of the samples in simulated body fluid for 4 weeks at a temperature of 37°C did not influence the compressive strength significantly. The sintered ceramics can be finished, for instance by grinding or polishing.