Micro Arc Oxidation of Wire Arc Sprayed Al-Mg6, Al-Si12, Al Coatings on Low Alloyed Steel

Levent Cenk Kumruoglu,Abdullah Mimaroglu,Ahmet Ozel,Fatih Ustel

doi:10.4236/eng.2011.37081

Abstract

Micro arc oxidation of wire arc sprayed Al-Mg6, Al-Si12 and Pure Al coatings on low carbon steel has been performed. The coatings have been analyzed using optic microscope, scanning electron microscopy, X-ray diffraction and surface roughness tester. At the same time, voltage and current regimes are investigated during the process. Then after MAO process, uniform Al2O3 ceramic coatings have been deposited on surface of Al-Mg6, Al-Si12 and Al coated steel. The ceramic coatings are mainly composed of Al2O3 phase. The compound coatings show high hardness and significant improvement of corrosion resistance property.

Highlights

IntroductionStudies focusing on how to improve the protection of steel against degradation by corrosion or wear are the main objective of researchers of processes and materials, always aiming to reduce costs by preserving the structure and increasing its service life
Studies focusing on how to improve the protection of steel against degradation by corrosion or wear are the main objective of researchers of processes and materials, always aiming to reduce costs by preserving the structure and increasing its service life.Cathodic and anodic protection, coatings and painting are some of the methods employed to combat degradation [1]
The purpose of this study was to explore the potential of the wire arc spray process in applying Al-Mg6, Al-Si12 and Pure Al coatings on low carbon steel and examination of micro arc oxidation of arc spray coatings

Summary

Introduction

Studies focusing on how to improve the protection of steel against degradation by corrosion or wear are the main objective of researchers of processes and materials, always aiming to reduce costs by preserving the structure and increasing its service life. Coatings and painting are some of the methods employed to combat degradation [1]. Micro Arc Oxidation (MAO), known as Plasma Electrolytic Oxidation, is globally gaining increased popularity as a novel means of deposition dense, thick, ultra-hard ceramic coatings on metals like Al, Mg, Ti, Zr and Nb and their alloys with an objective to improve the wear, thermal, chemical, corrosion, oxidation resistance. MAO process employs Electro-chemical and Electro-thermal oxidation in alkaline electrolytic medium with an alternating and direct current -high voltage surface multiple discharges [2,3]. The local instantaneous temperature and pressure inside these micro arc discharge channels can reach 103 - 104 K and 102 - 103 MPa, respectively [4]

Objectives

Methods

Results

Conclusion