351. Enhanced corrosion resistance and cellular behavior of ultrafine-grained biomedical NiTi alloy with a novel SrO–SiO2–TiO2 sol–gel coating
- Author
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Zheng, C.Y., Nie, F.L., Zheng, Y.F., Cheng, Y., Wei, S.C., Ruan, Liqun, and Valiev, R.Z.
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CORROSION resistant materials , *NICKEL-titanium alloys , *BIOMEDICAL materials , *SILICA , *TITANIUM dioxide , *METAL coating , *MECHANICAL properties of metals , *SHAPE memory effect - Abstract
Abstract: NiTi alloy has a unique combination of mechanical properties, shape memory effects and superelastic behavior that makes it attractive for several biomedical applications. In recent years, concerns about its biocompatibility have been aroused due to the toxic or side effect of released nickel ions, which restricts its application as an implant material. Bulk ultrafine-grained Ni50.8Ti49.2 alloy (UFG NiTi) was successfully fabricated by equal-channel angular pressing (ECAP) technique in the present study. A homogeneous and smooth SrO–SiO2–TiO2 sol–gel coating without cracks was fabricated on its surface by dip-coating method with the aim of increasing its corrosion resistance and cytocompatibility. Electrochemical tests in simulated body fluid (SBF) showed that the pitting corrosion potential of UFG NiTi was increased from 393mV(SCE) to 1800mV(SCE) after coated with SrO–SiO2–TiO2 film and the corrosion current density decreased from 3.41μA/cm2 to 0.629μA/cm2. Meanwhile, the sol–gel coating significantly decreased the release of nickel ions of UFG NiTi when soaked in SBF. UFG NiTi with SrO–SiO2–TiO2 sol–gel coating exhibited enhanced osteoblast-like cells attachment, spreading and proliferation compared with UFG NiTi without coating and CG NiTi. [Copyright &y& Elsevier]
- Published
- 2011
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