THIN HYDROXYAPATITE COATING PRODUCED BY THE ION-BEAM DYNAMIC MIXING METHOD

An ion beam dynamic mixing (IBDM) method was used to produce thin hydr oxyapatite coatings on titanium substrates. Structure, solubility and bond strength of coatings were evaluated. The hydroxyapatite-type stru cture was obtained from heat-treated coatings. As-coated coatings seem ed to be almost dissolved within 1 d in Hanks' solution. The thin laye r of films, however, was recognized with a firm intermediate compound (such as Ti3P4) to the substrate by X-ray photoelectron spectroscopy, indicating the high tensile bond strengths from the as-coated films. A lthough slight reductions of the bond strength were observed in heat-t reated specimens, the strengths were not reduced by immersion in Hanks ' solution for 30 d.