Depth-Resolved Strain Investigation of Plasma Sprayed Hydroxyapatite Coatings Exposed to Simulated Body Fluid

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Depth-Resolved Strain Investigation of Plasma Sprayed Hydroxyapatite Coatings Exposed to Simulated Body Fluid

T. Ntsoane, C. Theron, M. Topic, M. Härting, R. Heimann

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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


The article was published as article 19 of the book

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