Papers by Keyword: Biomimetic Deposition

Abstract: A two-step, biomimetic approach was applied for the rapid deposition of octacalcium phosphate (OCP) coatings on zirconia ceramics (Y-TZP). In the first step, sintered zirconia discs were immersed into a supersaturated Ca-P solution with pH=7.4 (CPS1). In the second step, the substrates were transferred from the CPS1 to another Ca-P solution with a lower pH (CPS2). After 6 hours of immersion in the CPS2, a thick coating consisting of large OCP crystals was obtained. Afterwards, the coated substrates were subjected to a thermal treatment in order to improve the attachment of the coating to the substrate.

Abstract: Biomimetic apatite deposition behaviors on Zr-1Nb and Ti-6Al-4V plate with various surface conditions were examined. Both alloys were polished with abrasive papers to have different roughness and some of them were treated in NaOH before deposition of apatites in the simulated body fluid. After, 10 days immersion in a SBF, NaOH treated Zr-1Nb and Ti-6Al-4V were completely coated with apatite. The deposition rate of apatite was higher on NaOH-treated Ti-6Al- 4V than on NaOH-treated Zr-1Nb initially, but the deposition rate on Zr-1Nb accelerated after 2 days and the total weight gain due to the deposition on Zr-1Nb approached to that of Ti-6Al-4V. NaOH treatment was found to enhance the deposition rate of apatite on Ti-6Al-4V significantly. On the other hand, the deposition rate of Zr-1Nb was not influenced by NaOH treatment. Without NaOH treatment, the polished Zr-1Nb with abrasive paper was found to induce more apatite nucleation than the polished Zr-6Al-4V. The presence of apatite was confirmed by XRD analysis. SEM observation revealed a conglomerated granular structure with elongate plates.