| Hydroxyapatite andβ-tricalcium phosphate are widely used as hard tissue substitute materials because their chemical composition and biological properties are similar to those of inorganic phase in bone. But hydroxyapatite is unable to biodegradate,β-tricalcium phosphate is biodegradable. Different biodegradation rates are required in various implant environments, so hydroxyapatite/β-tricalcium phosphate is developed by the stable hydroxyapatite and the solubleβ-tricalcium phosphate with the adjustable bioactivity and biodegradation, so that the degradation speed matches up to the formation speed of new bone and achieve clinical application.In this work, hydroxyapatite/β-tricalcium phosphate coatings were fabricated by a radio-frequency magnetron sputtering, and study sputtering technique, tissue, biodegradation and biocompatibility of coatings.Before sputtering, sputtering targets were successfully produced. Phases of those targets coincide with Phases of hydroxyapatite/β-tricalcium phosphate powder,and structure of those targets are uniform and density .The phase compositions,surface morphologies and Ca/P ratio of hydroxyapatite/β-tricalcium phosphate coatings were analyzed with X-ray Diffraction(XRD), scanning electron microscopy(SEM)and energy dispersive X-ray(EDS). The results show that the sputtered coatings are in amorphous state, and crystallinity of coatings is obviously improved after heat treatment. The surface of coatings are rather smooth and continuous. Ca/P ratio of 50HA/TCP coating is 1.70.Solubility of the coatings was measured in Hank's solution, and biocompatibility of the coatings was researched by cell culture. The results show that degradation speed of hydroxyapatite/β-tricalcium phosphate coatings increase with increasing ofβ-tricalcium phosphate content; cell attachment and proliferation of 50HA/TCP coating is better, cell attachment and proliferation ofβ-TCP coating is less.
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