Study on coloring of aluminum alloys by Microplasma oxidation (MPO) technique

Abstract

Over the past years, great scientific and industrial achievements have been made in the domain of existing many coloring technologies of aluminum alloys for different applications ,mostly, coloring after anodizing for decoration and physical applications. However, the coloring after anodizing process strongly depends on thickness and color of Al2O3 thin film , and on its porosity and their distribution which can affect the hardness of alumina layer. Also, this technology requires sequenced processes and controlled conditions to get the desired color. The MPO technology has recently been studied as a novel and effective means to provide improved properties such as thick and hard ceramic coating with excellent load-bearing and wear resistance properties on aluminum alloys. In the present study, the MPO technique was used for deposition of ceramic layers colored with different colors and hardness better than those produced by anodizing . This study is expected to promote the research in coloring of aluminum alloys so as to meet the increased demands for colored aluminum alloys for hard environmental applications ,where, such know-how can not be gained easily from the literature and the internet.