Depth-Resolved Strain Investigation of Plasma Sprayed Hydroxyapatite Coatings Exposed to Simulated Body Fluid
T. Ntsoane, C. Theron, M. Topic, M. Härting, R. Heimanndownload PDF
The influence of exposure to simulated body fluid (SBF) on plasma sprayed hydroxyapatite (HAp) coatings on medical grade Ti6Al4V samples has been investigated. Through-thickness residual strain investigations of HAp coatings deposited on flat substrate surfaces incubated for 7, 28 and 56 days were performed using high-energy synchrotron diffraction techniques. In the as-sprayed condition, the results show the top half of the HAp coating to be under compression with the maximum around the near-surface region, relaxing with depth below the surface reaching a strain-free point around the coating thickness midpoint. On the contrary, the remainder of the coating is under tension increasing with further depth; the maximum tension is observed near the coating-substrate interface region. Upon immersion in SBF, both the slope of the normal strain components 11 and 33 relax, with the former experiencing a change in slope before saturating after 7 days; the highest change was observed within the first week of incubation.
Plasma-Sprayed Hydroxyapatite Coatings, In-Vitro Investigation, High-Energy Diffraction, Residual Stress
Published online 4/20/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: T. Ntsoane, C. Theron, M. Topic, M. Härting, R. Heimann, ‘Depth-Resolved Strain Investigation of Plasma Sprayed Hydroxyapatite Coatings Exposed to Simulated Body Fluid’, Materials Research Proceedings, Vol. 4, pp 123-114, 2018
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