Tough and adhesive nanostructured calcium phosphate thin films deposited by the pulsed plasma deposition method

Abstract

Calcium phosphate thin films were deposited at room temperature by the pulsed plasma deposition method. After annealing at 600 °C, film mechanical properties and adhesion to the titanium substrate strongly improved.

The Pulsed Electron Deposition Technique for Biomedical Applications: A Review

“…The treatment led to crystalline HA and improved the mechanical properties of the film compared to the nearly amorphous as-deposited one, for instance leading to increased elastic strain to failure, resistance to plastic deformation, and adhesion to the substrate. Besides, no significant differences were found in terms of cytotoxicity between as-deposited and treated films, both being capable of subtly promoting adhesion and proliferation of primary osteoblast cells [58].…”

“…In this context, PED technology has been tested for the deposition of nanostructured bioactive thin films on metallic and polymeric implants. In a first study, CaP films were deposited on titanium alloy substrate by ablating a sintered HA target; the analysis of morphology, microstructure and in vitro cytotoxicity were carried out focusing in particular on the effect of the post deposition thermal treatment performed at 600 • C for 1 h [58]. The treatment led to crystalline HA and improved the mechanical properties of the film compared to the nearly amorphous as-deposited one, for instance leading to increased elastic strain to failure, resistance to plastic deformation, and adhesion to the substrate.…”

“…Nevertheless, some crucial aspects concerning the quality of the coatings fabricated by PED still deserve deeper investigation. For instance, whereas crystalline coatings can be easily deposited by PED from target materials exhibiting simple chemical composition (i.e., ZrO 2 ) [15], this results in more challenges when complex or multiphase materials (i.e., calcium phosphates) are involved [58,73]. In these cases, the achievement of correct crystallinity (close to that of natural bone apatite), and therefore, also of optimal mechanical properties (coating toughness, hardness, and adhesion) still requires a post deposition thermal treatment.…”

Ceramic coatings for orthopaedic implants: preparation and characterization

“…Also, the presence of CaO crystallites was evidenced by the Bragg peaks observed at 32.5° and 37.4° together with a small amount of Ca(OH) 2 crystallites generating a peak at 28.45°. After annealing in air for 1 h at 600 °C, a polycrystalline film was obtained with all the main peaks of crystalline HA . However, the low signal of CaO crystallites was still registered after annealing.…”

“…In the present work, we have investigated also the surface chemistry of HA films as deposited by PPD and annealed at 600 °C, as a valuable alternative to conventional thick‐sprayed HA coatings . Finally, we investigated also the magnetic HA coatings, as magnetic scaffolds have been already proved to be capable to promote bone‐cell adhesion, proliferation and differentiation …”