title: Microstructure and corrosion behavior of laser surface-treated AZ31B Mg bio-implant material.
abstract: Although magnesium and magnesium alloys are considered biocompatible and biodegradable, they suffer from poor corrosion performance in the human body environment. In light of this, surface modification via rapid surface melting of AZ31B Mg alloy using a continuous-wave Nd:YAG laser was conducted. Laser processing was performed with laser energy ranging from 1.06 to 3.18 J/mm2. The corrosion behavior in simulated body fluid of laser surface-treated and untreated AZ31B Mg alloy samples was evaluated using electrochemical technique. The effect of laser surface treatment on phase and microstructure evolution was evaluated using X-ray diffraction and scanning electron microscopy. Microstructure examination revealed grain refinement as well as formation and uniform distribution of Mg17Al12phase along the grain boundary for laser surface-treated samples. Evolution of such unique microstructure during laser surface treatment indicated enhancement in the corrosion resistance of laser surface-treated samples compared to untreated alloy.
authors.affiliation: Laboratory of Laser Additive and Subtractive Manufacturing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, 76203, USA.
authors.forename: Tso-Chang
authors.initials: TC
authors.lastname: Wu
authors.affiliation: Laboratory of Laser Additive and Subtractive Manufacturing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, 76203, USA.
authors.forename: Yee-Hsien
authors.initials: YH
authors.lastname: Ho
authors.affiliation: Laboratory of Laser Additive and Subtractive Manufacturing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, 76203, USA.
authors.forename: Sameehan S
authors.initials: SS
authors.lastname: Joshi
authors.affiliation: Laboratory of Laser Additive and Subtractive Manufacturing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, 76203, USA.
authors.forename: Ravi S
authors.initials: RS
authors.lastname: Rajamure
authors.affiliation: Laboratory of Laser Additive and Subtractive Manufacturing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, 76203, USA. Narendra.Dahotre@unt.edu.
authors.forename: Narendra B
authors.initials: NB
authors.lastname: Dahotre
mesh_terms: D000497:Alloys / Q000737:chemistry* / Q000528:radiation effects*; D001672:Biocompatible Materials / Q000737:chemistry* / Q000528:radiation effects*; D003343:Corrosion; D055664:Electrochemical Techniques; D006801:Humans; D007834:Lasers; D008274:Magnesium / Q000737:chemistry* / Q000528:radiation effects*; D008422:Materials Testing / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D019736:Prostheses and Implants; D013499:Surface Properties; D014961:X-Ray Diffraction
chemical_list: C000621732:AZ31B alloy; D000497:Alloys; D001672:Biocompatible Materials; D008274:Magnesium
keywords: AZ31B Mg alloy; Bio-implant; Corrosion; Laser surface melting; Mg17Al12 β-phase