Effects of technological parameters on the microstructure of laser remelted hydroxyapatite (HA) coatings

Abstract

In this paper, the influence of different laser power and scanning speed on the microstructure of laser remelted as-sprayed hydroxyapatite (HA) coatings was studied and the optimum technological parameters were obtained. The morphologies, elements and phase analysis of both sprayed and remelted coatings were examined by means of electron probe microanalysis, x-ray diffraction and so on. The results show that the plasma sprayed coatings could be improved by laser remelting and the optimum technological parameters are that the laser power is 600 W and the scanning speed is 11.2 mm s−1. In the technological condition, the remelted coating which has compact columnar and cellular dendritic crystal consists of HA, α-TCP, CaO and TiO2 phases, and the Ca/P ratio of the coating is the most approximate to that of HA. When increasing the laser power and slowing the scanning speed, the structure of the coating will become much coarser and the Ca/P ratio will deviate more from that of HA. On the contrary, if the laser power is reduced and the scanning speed is accelerated, the influence of technological parameters of laser remelting on the sprayed coating will be weakened.

Bioactive bredigite coating with improved bonding strength, rapid apatite mineralization and excellent cytocompatibility

“…Many studies have been conducted to improve the performance of HA coating. Post-treatments, like water vapor treatment, 7–9 heat treatment 10,11 and laser treatment 12,13 were adopted to improve the stability of HA coating. Plasma-sprayed grade coatings, 14–17 composite coatings 18–20 and bond coatings 21–23 were prepared with the incorporation of Ti, Ti-6Al-4 V, titania (TiO 2 ) and zirconia as reinforcing additives, showing improved bonding strength.…”