Biomimetic Coating of Precalcified Ti-6Al-4V Alloy

ABSTRACT

Calcium hydroxyapatite, HA, (Ca10(PO4)6(OH)2) bioceramics, owing to their similarity with the human bone and dentin minerals, attract significant interest for orthopaedic and dental applications. Biological apatites, on the other hand, are carbonate substituted and calcium-deficient. Biomimetic coating of titanium and related alloys with carbonated apatitic calcium phosphate is an important area of research in implantology. While this paper specifically refers to coating Ti-6Al-4V, (TAV) the obtained results are valid with other related alloys as well.

An attempt was made in the current research to accelerate the biomimetic coating process through precalcification of the alkali and heat treated alloy. The precalcification resulted in a homogenous layer of calcium precursors on the surface of the alloys. Such precursors accelerated the biomimetic deposition of carbonate hydroxyapatite (CHA) coat resembling that of the biomineral apatite upon soaking in Kukubo corrected simulated body fluid (1.5 x c-SBF). The development of coats on Ti-6Al-4V surfaces were assessed by step by step diffuse reflectance infra-red spectroscopy and scanning electron microscopy.

The essential information of biodeposition was obtained by following the uptake or release of calcium and inorganic phosphorus, Ca, iP, ionic species biochemically and mirrored by parallel electrical conductivity measurements of the soaking solutions.