title: Corrosion and bioactivity performance of graphene oxide coating on TiNb shape memory alloys in simulated body fluid.
abstract: In the present work, the microstructure, corrosion, and bioactivity of graphene oxide (GO) coating on the laser-modified and -unmodified surfaces of TiNb shape memory alloys (SMAs) were investigated. The surface morphology and chemical composition was examined using field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The surface modification was carried out via a femtosecond laser with the aim to increase the surface roughness, and thus increase the adhesion property. FE-SEM analysis of the laser-treated Ti-30at.% Nb revealed the increase in surface roughness and oxygen/nitrogen containing groups on the Ti-30at.% Nb surface after being surface modified via a femtosecond laser. Furthermore, the thickness of GO was increased from 35μm to 45μm after the surface was modified. Potentiodynamic polarisation and electrochemical impedance spectroscopy studies revealed that both the GO and laser/GO-coated samples exhibited higher corrosion resistance than that of the uncoated TiNb SMA sample. However, the laser/GO-coated sample presented the highest corrosion resistance in SBF at 37°C. In addition, during soaking in the simulated body fluid (SBF), both the GO and laser/GO coating improved the formation of apatite layer. Based on the bioactivity results, the GO coating exhibited a remarkable antibacterial activity against gram-negative bacteria compared with the uncoated. In conclusion, the present results indicate that Ti-30at.% Nb SMAs may be promising alternatives to NiTi for certain biomedical applications.
authors: Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia; Faculty of Information Science and Engineering, Management and Science University, 40100 Shah Alam, Malaysia. Electronic address: safaaengineer@gmail.com.
authors: Safaa N
authors: SN
authors: Saud
authors: Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors: Raheleh
authors: R
authors: Hosseinian S
authors: Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia; Advanced Materials Research Center, Faculty of Materials Engineering, NajafAbad Branch, Islamic Azad University, NajafAbad, Iran.
authors: H R
authors: HR
authors: Bakhsheshi-Rad
authors: Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310, UTM, Skudai, Johor, Malaysia.
authors: F
authors: F
authors: Yaghoubidoust
authors: Medical Devices & Technology Group (MEDITEG), Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia.
authors: N
authors: N
authors: Iqbal
authors: Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia.
authors: E
authors: E
authors: Hamzah
authors: Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors: C H Raymond
authors: CHR
authors: Ooi
mesh_terms: D000497:Alloys / Q000737:chemistry*; D001826:Body Fluids / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003343:Corrosion; D006090:Gram-Negative Bacteria / Q000254:growth & development; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D054802:Molecular Imprinting; D009556:Niobium / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; D020099:Coated Materials, Biocompatible; D009556:Niobium; D006108:Graphite; D014025:Titanium
keywords: Bioactivity; Corrosion; Femtosecond laser; Graphene oxide; Ti–Nb