• Antibacterial
• Coatings
• Cold gas spray
• Hydroxyapatite
• Silver

Ag-doped HA antibacterial coatings deposited by cold spraying are developed during the thesis activity. This thermal spray technique is a solid-state process based on low temperature and kinetics energy. Hydroxyapatite (Ca10(PO4)6(OH)2) is the primarily mineral phase of bones and teeth and enhances biomedical implants because of its bioactivity and osteoconductivity properties.
In this work HA is mixed with two powders containing Ag, Zinc oxide and titanium oxide. Powder preparation is needed to adequate flowability, shape and size distribution of raw materials in order to be successfully sprayed.
For the coating production, a Ti bond coat has been produced through HP-CGS to rough the surface and improve the ceramic coating adhesion. Then, LP-CGS has been used to deposit the ceramic top coat, modifying different process parameters such as temperature and feed rate to optimize the final deposition. The coatings have been characterized by Scanning Electron Microscopy (SEM) to analyse thickness and morphology and by EDS to evaluate the silver distribution. In order to check biological properties of the coatings, tests of cytotoxicity, silver dissolution, and in vitro evaluation for apatite-forming ability have been also developed.

Ag-doped HA antibacterial coatings deposited by cold spraying are developed during the thesis activity. This thermal spray technique is a solid-state process based on low temperature and kinetics energy. Hydroxyapatite (Ca10(PO4)6(OH)2) is the primarily mineral phase of bones and teeth and enhances biomedical implants because of its bioactivity and osteoconductivity properties. In this work HA is mixed with two powders containing Ag, Zinc oxide and titanium oxide. Powder preparation is needed to adequate flowability, shape and size distribution of raw materials in order to be successfully sprayed. For the coating production, a Ti bond coat has been produced through HP-CGS to rough the surface and improve the ceramic coating adhesion. Then, LP-CGS has been used to deposit the ceramic top coat, modifying different process parameters such as temperature and feed rate to optimize the final deposition. The coatings have been characterized by Scanning Electron Microscopy (SEM) to analyse thickness and morphology and by EDS to evaluate the silver distribution. In order to check biological properties of the coatings, tests of cytotoxicity, silver dissolution, and in vitro evaluation for apatite-forming ability have been also developed.