Technology of Coating Deposition

The Influence of Calcium Phosphate Structure on the Surface Charge Produced in an Electric Field

“…Compared to natural bone, HAp has low mechanical strength, therefore, in order to implant it in load-bearing sites and improve its mechanical properties, it is necessary to form coatings [23], using biocompatible materials with good mechanical properties as substrates, such as titanium. For the production of HAp coatings, thermal spraying methods are widely used, for example, flame spraying, during which the material placed in the flame is melted and sprayed at a high speed against the surface to be coated [24], any thermally stable material with a precisely defined melting point can be coated in this way, on almost any surface. However, due to the high spraying temperature (above 3000 °C), molten HAp particles can undergo thermal decomposition into TCP, TTCP, or CaO, and the formation of the ACP phase [25], as well as dehydroxylation, leading to the release of OHand the formation of oxyhydroxyapatite (OHAp) [26].…”