Effects of titanium surface treatment on adhesive properties of hydroxyapatite ceramics coating to titanium substrates by double layered capsule hydrothermal hot-pressing

Abstract

This report described the effects of Ti surface modification with NaOH hydrothermal solution on adhesion strength of HA coating produced by newly developed hydrothermal (DC-HHP) method. 2 kinds of surface layer (containing anatase-type TiO 2 or not) were formed on Ti surface by immersing to 5 mol/L NaOH solution before HA coating process. Pull out tests were conducted to obtain an estimate for the adhesion properties of the HA coating. Shear strength of specimens with 5 mol/L NaOH treated at 423 K for 2 hours was estimated in the range of 4.15.7 MPa. The enhancement of the HA adhesive properties as well as more than three times values was achieved, in comparison to the specimens without the surface layer (approximate 1.5 MPa). It was demonstrated that 423 K hydrothermal treatment with 5 mol/l NaOH solution on Ti surfaces is significantly effective to enhancing adhesion strength of the HA coating produced by the DC-HHP method.

Cold sintering of ceramics and glasses: A review

“…Between inner and outer capsule, alumina powder is placed to maintain the space for water retreat. Hydroxyapatite-coated magnesium [129], and titanium [133,134,189], were produced by using DC-HHP.…”

Calcium orthophosphate deposits: Preparation, properties and biomedical applications

“…Just a few publications were found on the topic and they were devoted to HA deposition on AZ31 Mg alloy [562] and Ti [9,563,564]. In order to create suitable hydrothermal conditions, double-layered capsules were used: the inner capsule encapsulated the deposited materials and a substrate, while the outer one was subjected to isostatic pressing under the hydrothermal conditions.…”

“…These results also revealed that a crack propagation occurred within the HA deposits but not along the HA/Ti interface. Therefore, the fracture property of the HA/Ti interface was higher than that of the HA bioceramics only[9,563,564].4.4.3. Detonation gun sprayingDetonation gun spraying is both a high temperature and a high velocity technique, which introduced a higher degree of melting to starting powder.…”

There Are over 60 Ways to Produce Biocompatible Calcium Orthophosphate (CaPO4) Deposits on Various Substrates

“…There are only a few publications on the subject and they are devoted to HA deposition on AZ31 Mg alloys [620] and Ti [9,621,622]. A double-layer capsule was used to create suitable hydrothermal conditions: the inner capsule encapsulated the deposited material and substrate, while the outer capsule was subjected to hydrostatic pressing under hydrothermal conditions.…”