The preparation of calcium phosphate coatings on titanium and nickel–titanium by rf-magnetron-sputtered deposition: Composition, structure and micromechanical properties
- 作者：V.F. Pichugin ; R.A. Surmenev ; E.V. Shesterikov ; M.A. Ryabtseva ; E.V. Eshenko ; S.I. Tverdokhlebov ; O. Prymak ; M. Epple
- 关键词：Calcium phosphate coating ; rf-magnetron sputtering ; Adhesion strength
- 刊名：Surface and Coatings Technology
- 出版年：2008
- 期刊代码：106_02578972
- 类别：ms
- 出版时间：15 May 2008
- 卷：202
- 期：16
- 页码：3913-3920
- 文件大小：932 K
摘要
Thin calcium phosphate coatings with a thickness of 0.09 to 2.7 µm were prepared by radio-frequency magnetron sputtering deposition on NiTi and Ti substrates at a substrate temperature of 500 °C in argon atmosphere. Scanning electron microscopy (SEM) showed that the surface structure is uniform and dense without visible defects (pores and microcracks). Rutherford backscattering spectroscopy (RBS) and energy-dispersive X-ray spectroscopy (EDX) confirmed that the coating contains calcium, phosphorus, and oxygen with a uniform composition. Crystallographically, the coating consists of crystalline hydroxyapatite which is also supported by infrared spectroscopy. The mechanical characteristics of the coating were measured by nanoindentation (Vickers indenter), giving a nanohardness of 10 GPa and a Young's modulus of 110 GPa. The strength of adhesion of the calcium phosphate coating to the metallic substrates depended on the coating's thickness and decreased for a thickness larger than 1.6 µm. No difference was observed between NiTi and Ti substrates.