کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5364289 1388314 2007 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Characterization and corrosion studies of titania-coated NiTi prepared by sol-gel technique and steam crystallization
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Characterization and corrosion studies of titania-coated NiTi prepared by sol-gel technique and steam crystallization
چکیده انگلیسی

Nickel titanium (NiTi) was dip-coated with titania via the sol-gel route using titanium butoxide (Ti(OC4H9)4) as precursor. The as-coated titania film was crystallized to form anatase by treatment in steam at 105 °C. The crystallized film was relatively thick (about 750 nm) and even. Atomic force microscopy (AFM) revealed that the film was dense with a surface roughness of about 3 nm, and was composed of particles of about 100 nm. X-ray diffractometry (XRD) showed that these particles were composed of nanocrystallites of a few nanometers. Nanoindentation tests of the titania film indicated that the film was tough, possibly due to the nano-size of the crystallites. The mean hardness H and elastic modulus E of the coating were about 1.5 and 70 GPa, respectively. Direct pull-off test recorded a mean coating-substrate bonding strength larger than 17 MPa. Electrochemical impedance spectroscopic (EIS) study and cyclic polarization tests showed that the corrosion resistance of the coated NiTi samples in Hanks' solution was increased by about two orders of magnitude compared with the substrate. Taken together, the present study showed that steam crystallization is a feasible low-temperature treatment method for sol-gel derived titania coating on NiTi in biomedical applications.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Surface Science - Volume 253, Issue 16, 15 June 2007, Pages 6762-6768
نویسندگان
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