WAY OF OBTAINING HIGH DENSITY BIO CERAMIC MATERIALS BASED ON CALCIUM PHOSPHATE BY THE PARALLEL OPTIMIZATION OF THE SYNTHESIS METHOD AND THE SINTERING PROCESS

摘要

Invention herewith described refers to the way of obtaining high density bio ceramic materials based on calcium phosphate by the parallel optimization of the synthesis method and the sintering process. By the controlled methods of synthesis, chemical precipitation and hydrothermal processing at temperature of 200°C, there had been synthesized hydroxyapatite nanopowders, which were later processed by the methods of the conventional and the two-stage sintering. At the different sintering conditions there were obtained high density bio ceramic materials suitable for the reconstruction of the bone tissue. The chemical composition of the obtained materials comprises samples of pure hydroxyapatite and hydroxyapatite composite and α-tricalcium phosphate, and hydroxyapatite and &bgr;-tricalcium phosphate, with an average particle size from the nanometric to the micrometric level. By the method of two-stage sintering, in the conditions of the first stage temperature of 900°C, with detention time of 5 min and the second stage temperature of 850°C, with detention time of 20 h, there is obtained the pure hydroxyapatite, which has a theoretical density, particles with narrow size distribution with the average value of 75 nm. Such material is competitive with currently existing materials obtained by the methods of sintering in the presence of external fields that involve the use of significantly more expensive and complex equipment.