Corrosion Control in the Coating Process of Mg Alloys

Abstract The biocompatibility, mechanical properties and biodegradable nature of Mg alloys have made them attractive for biomedical applications, especially as bone implants. However, one of the main problems that limit the use of Mg alloy for several biomedical applications is their fast corrosion rates inside the body. Coating Mg-based implants is one of the most extensively studied approaches to address the fast corrosion rates of Mg alloys in the physiological environment. Micro arc oxidation (MAO) coating process has shown very promising results towards reducing the corrosion rates of Mg alloys due to the formation of a protective dense, well-adhered and wear-resistant oxide layer on the surface of the Mg alloy. In this study, the feasibility of coating an Mg-Zn-Ca-based alloy with a composite coating made using a micro-arc oxidation coating process and an immersion (dipping process) was investigated. The corrosion properties and surface characteristics of the coated alloy samples are assessed. The created protective composite coating is used to slow the corrosion rates of an Mg-Zn-Ca-based alloy. The developed composite coating resulted in a significant reduction in the corrosion rates. The results of this study show that it is possible to achieve more controlled corrosion rates of Mg-based implants towards patient-specific bone implant applications.

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Electron-Probe Quantitative Energy-Dispersive Analysis of Trace Magnesium Concentrations in Ag-Mg Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016501x ◽

1996 ◽

Vol 54 ◽

pp. 510-511

Author(s):

R. B. Marinenko

Keyword(s):

Electron Probe ◽

Energy Dispersive Spectrometry ◽

Mg Alloys ◽

Energy Dispersive ◽

Energy Dispersive Analysis ◽

High Tc ◽

Alloy Wire ◽

High Tc Superconductor ◽

Eds Analysis ◽

Superior Mechanical Properties

Internally oxidized Ag-Mg alloys are used as sheaths for high Tc superconductor wires because of their superior mechanical properties. The preparation and characteristics of these materials have been reported. Performance of the sheaths depends on the concentration of the magnesium which generally is less than 0.5 wt. percent. The purpose of this work was to determine whether electron probe microanalysis using energy dispersive spectrometry (EDS) could be used to quantitate three different Ag-Mg alloys. Quantitative EDS analysis can be difficult because the AgL escape peak occurs at the same energy (1.25 keV) as the Mg Kα peak. An EDS spectrum of a Ag-Mg alloy wire is compared to a pure Ag spectrum in Fig. 1.

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Characterization of oxide films for corrosion control

Matériaux & Techniques ◽

10.1051/mattech/200391120126s ◽

2003 ◽

Vol 91 ◽

pp. 126-128

Author(s):

Yoshinori Yomura

Keyword(s):

Oxide Films ◽

Corrosion Control

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Economics of coated paper production made from deinked pulp

TAPPI Journal ◽

10.32964/tj12.4.19 ◽

2013 ◽

Vol 12 (4) ◽

pp. 19-27

Author(s):

PATRICK HUBER ◽

LAURENT LYANNAZ ◽

BRUNO CARRÉ

Keyword(s):

Mechanical Properties ◽

Optimization Methods ◽

Coating Process ◽

Coated Paper ◽

Paper Production ◽

Base Paper

The fraction of deinked pulp for coated paper production is continually increasing, with some mills using 100% deinked pulp for the base paper. The brightness of the coated paper made from deinked pulp may be reached through a combination of more or less extensive deinking, compensated by appropriate coating, to optimize costs overall. The authors proposed general optimization methods combined with Kubelka-Munk multilayer calculations to find the most economical combination of deinking and coating process that would produce a coated paper made from DIP, at a given target brightness, while maintaining mechanical properties.

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Depletion of coating color components in the blade coating process circulation

TAPPI Journal ◽

10.32964/tj10.9.17 ◽

2011 ◽

Vol 10 (9) ◽

pp. 17-23 ◽

Cited By ~ 1

Author(s):

ANNE RUTANEN ◽

MARTTI TOIVAKKA

Keyword(s):

Fine Particles ◽

Particle Density ◽

Stable Process ◽

Size Fraction ◽

Color Stability ◽

Strong Interactions ◽

Coating Process ◽

Size Segregation ◽

Coating Color ◽

Average Size

Coating color stability, as defined by changes in its solid particle fraction, is important for runnability, quality, and costs of a paper coating operation. This study sought to determine whether the size or density of particles is important in size segregation in a pigment coating process. We used a laboratory coater to study changes in coating color composition during coating operations. The results suggest that size segregation occurs for high and low density particles. Regardless of the particle density, the fine particle size fraction (<0.2 μm) was the most prone for depletion, causing an increase in the average size of the particles. Strong interactions between the fine particles and other components also were associated with a low depletion tendency of fine particles. A stable process and improved efficiency of fine particles and binders can be achieved by controlling the depletion of fine particles.

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