Paper Title:
Effects of Hypophosphate Concentrations on the Characteristics of Micro-Arc Oxidation Coatings Formed on Biomedical NiTi Alloy
  Abstract

Microarc oxidation coatings on biomedical NiTi alloy were prepared in aluminate electrolytes with and without hypophosphate addition. The effect of hypophosphate concentrations on the characteristics of micro-arc oxidation coatings has been studied. The compositions and surface morphologies of the coatings prepared in different hypophosphate concentrations were determined by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Surface roughness (Ra) and bonding strength of the coatings were measured by surface roughmeter and a direct pull-off test, respectively. The corrosion resistance of the coatings was evaluated in Hank’s solution using potentiodynamic polarization tests. The results show that all of the coatings exhibit a typical porous surface structure and mainly consist of γ-Al2O3 crystal phase. With increasing the hypophosphate concentrations, the elemental contents of Ni, Ti and P increase while Al decreases; the pore sizes and surface roughness of the coatings decrease firstly, reaching a minimum value at 0.01mol/L, and then increase; at the same time, the bonding strength increases up to 60MPa, and then decreases. The corrosion resistance of the coatings decreases with the increase of the hypophosphate concentrations, but all of the coated samples is better than that of the uncoated NiTi alloy.

  Info
Periodical
Advanced Materials Research (Volumes 314-316)
Chapter
Surface Engineering/Coatings
Edited by
Jian Gao
Pages
240-244
DOI
10.4028/www.scientific.net/AMR.314-316.240
Citation
J. L. Xu, J. M. Luo, F. Liu, "Effects of Hypophosphate Concentrations on the Characteristics of Micro-Arc Oxidation Coatings Formed on Biomedical NiTi Alloy", Advanced Materials Research, Vols. 314-316, pp. 240-244, 2011
Online since
August 2011
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: N. R. Ha, Z. X. Yang, Kyu Hong Hwang, J. K. Lee
Abstract:Pure Titanium alloys are superiorities of biocompatibility, mechanical properties and chemical stability. The biocompatibility of Ti alloy...
177
Authors: Cui Li, Wei Qi, Kutsuna Muneharu
Abstract:A zircon coating was applied on the surface of Ti-6Al-4V alloy by plasma spray and its effect on the high temperature tensile properties of...
547
Authors: Wen Feng Qin, Jiang Long, Feng Liu
Abstract:The surface morphology and hardness of electroless Ni–P alloy plating on 6061 aluminum alloys substrate in an alkaline plating bath with...
293
Authors: Li Zhen Wang, Yan Juan Han, Kai Qing Zhang, Kun Wang
Abstract:The electrochemical behaviors of zinc electrode containing Bi, In and Al were tested to study aluminum acting on the electrochemical...
590
Authors: Hsi Hsin Chien, Kung Jeng Ma, Chien Hung Kuo
Chapter 3: Mechanical Engineering and Manufacturing
Abstract:Glass molding process provides a great potential for the production of precise glass optical components at low cost. The platinum-iridium...
533