title: Effect of laser polishing on the surface roughness and corrosion resistance of Nitinol stents.
abstract: In this paper, we investigated the effect of laser polishing at different treatment times on the surface roughness and corrosion resistance of a biliary nickel-titanium (NiTi or Nitinol) stent. A specific area of the stent wire surface was checked for changes in roughness by scanning electron microscopy (SEM) and a noncontact profilometer. The corrosion resistance was assessed by potentiodynamic polarization test and electrochemical impedance spectroscopy. The surface characterization revealed that laser polishing reduced the surface roughness of stent by 34-64% compared to that of the as-received stent surface condition depending on the treatment time (i.e., 700-1600 μm). Measurements using potentiodynamic polarization in simulated body fluid solution showed better anti-corrosion performance of laser-polished stent compared to magnetically-polished stent and has comparable corrosion resistance with the as-received stent condition. In this paper, we have shown a preliminary study on the potential of laser polishing for the improvement of surface roughness of stent without affecting much its corrosion resistance.
authors.affiliation: Department of Bionanosystem Engineering, Chonbuk National University, Jeonju, Korea.
authors.forename: Chan-Hee
authors.initials: CH
authors.lastname: Park
authors.affiliation: Division of Mechanical Design Engineering, Chonbuk National University, Jeonju, Korea School of Civil and Environmental Engineering, University of Technology, Sydney (UTS), Sydney, Australia.
authors.forename: Leonard D
authors.initials: LD
authors.lastname: Tijing
authors.affiliation: Department of Bionanosystem Engineering, Chonbuk National University, Jeonju, Korea Department of Engineering Science and Humanities, Institute of Engineering, Pulchowk Campus, Tribhuvan University, Kathmandu, Nepal.
authors.forename: Hem Raj
authors.initials: HR
authors.lastname: Pant
authors.affiliation: Department of Bionanosystem Engineering, Chonbuk National University, Jeonju, Korea Division of Mechanical Design Engineering, Chonbuk National University, Jeonju, Korea.
authors.forename: Cheol Sang
authors.initials: CS
authors.lastname: Kim
mesh_terms: D000497:Alloys / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry; D058266:Dielectric Spectroscopy; D004563:Electrochemistry; D004867:Equipment Design; D021621:Imaging, Three-Dimensional; D007834:Lasers; D008280:Magnetics; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011199:Potentiometry; D015607:Stents; D013499:Surface Properties
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; C013616:nitinol
keywords: Alloys; biomaterials; corrosion test; microstructure; surface properties