Microstructure and surface characteristics of hydroxyapatite coating on titanium and Ti-30Nb-1Fe-1Hf alloy by anodic oxidation and hydrothermal treatment

Calcium orthophosphate deposits: Preparation, properties and biomedical applications

“…The deposits were found to consist of CDHA-based outer layer and TiO 2 -based inner layer, in which the outer layer contained small amounts of α-TCP and CaCO 3 , while the inner layer contained CaTiO 3 [549]. Similar results were obtained in another study [550].…”

“…The authors suggested that the hydrothermal treatment forced ACP diffusion from the inner layers into the surface, where it was hydrolyzed and precipitated as HA [547]. Similar results were obtained for Ti alloys [550][551][552]. However, when aqueous electrolytes containing dissolved CaCl 2 and KH 2 PO 4 were used, CaPO 4 was deposited without a necessity to perform additional treatments [548].…”

“…In addition, the MAO process could be performed in aqueous electrolytes, containing dissolved Ca-and PO 4 -containing compounds only [542][543][544][545][546][547][548][549][550][551][552][553]. In this case, CaPO 4 was deposited in the single stage.…”

Modification of niobium surfaces using plasma electrolytic oxidation in silicate solutions

“…This step can be omitted when the surface of the implant is bioactive, which means that it can actively form a permanent fixation with treated bone [28,29]. To accomplish this goal, a wide variety of surface modification methods have been developed [29], including plasma spraying [30], glow discharge plasma treatment [31], ion implantation/deposition [32], physical vapour deposition, chemical vapour deposition, alkali treatment [33,34], sol-gel coatings [35] and electrochemical methods.…”

“…The goal of this processing technique is to thicken the naturally occurring passive metal oxide layer using the flow of electric current through a standard electrolytic system composed of an anode (the workpiece), cathode, electrolysis cell filled with an electrolyte solution and a power supply [20,27,29,30]. In general, anodic oxidation can be conducted under two distinct conditions.…”