HA/beta-TCP plasma sprayed coatings on Ti substrate for biomedical applications

摘要

The present work focuses on the fabrication of beta TCP (beta-tricalcium phosphate) and HA/beta TCP (hydroxyapatite/ beta-tricalcium phosphate) composite coatings by plasma spraying. The starting powders were produced via solidstate method using 2 wt% MgO to stabilize beta TCP phase. The synthesized powders were preliminarily granulated to be used by the plasma spray process. Coatings obtained on titanium substrates are uniform and well adherent but due to the high temperature and cooling rate typical for plasma spraying process, beta TCP phase is almost totally transformed into the alpha allotrope. Thermal treatment at 800 degrees C allows the reconversion of the phase alpha TCP - beta TCP. It is therefore possible to produce coatings with tuneable dissolution properties by selecting the proper initial powder mixture and the specific thermal treatment.