Investigation on surface properties of AZ31 magnesium alloy modified by micro-arc oxidation and cathodic deposition techniques

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS Surface & Coatings Technology Pub Date : 2024-11-28 DOI:10.1016/j.surfcoat.2024.131599

Hongkang Pan , Honghua Hu , Zhonghua Wei , Fan Yang , Zhanshuai Fan , Hailin Lu

{"title":"Investigation on surface properties of AZ31 magnesium alloy modified by micro-arc oxidation and cathodic deposition techniques","authors":"Hongkang Pan , Honghua Hu , Zhonghua Wei , Fan Yang , Zhanshuai Fan , Hailin Lu","doi":"10.1016/j.surfcoat.2024.131599","DOIUrl":null,"url":null,"abstract":"<div><div>Cathodic deposition (CD) technology, as a surface treatment technology, is widely used to prepare surface protective layers of non-valve metals. However, due to the presence of a dense oxide film on the surface of valve metal, during the CD process, this dense oxide film will hinder the contact between ions in the electrolyte and the substrate surface, making CD deposition technology unsuitable for valve metal. In this paper, valve metal AZ31 Mg alloy was first treated by micro-arc oxidation (MAO) technology, and then CD treatment was performed using ethylene glycol organic solution as electrolyte. This method not only solves the problem that CD technology cannot be applied to valve metals and successfully prepares a coating with excellent friction and corrosion resistance, but also explores a new solution as a CD electrolyte. By comparing with the samples after CD treatment in deionized water solution and the samples after MAO, the results show that after CD treatment in deionized water solution, only the porosity (8.572 %) and coefficient of friction (COF) (0.403) of the coating were improved, but after CD treatment in ethylene glycol solution, the coating surface had the lowest porosity (4.263 %), the highest hardness (265.2 HV), and the smallest COF (0.362). Electrochemical tests further showed that the sample had the lowest corrosion current density (5.6099 × 10<sup>−10</sup> A/cm<sup>2</sup>) after CD treatment in ethylene glycol electrolyte. The coating prepared by this method can be widely used in aerospace, medical equipment and other fields due to their excellent friction and corrosion resistance, and can increase the service life of Mg alloy parts. However, this method is currently more suitable for the processing of small parts. This study not only provides a valuable strategy for improving the performance of MAO coatings, but also provides a new direction for the application of CD technology on valve metals.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"496 ","pages":"Article 131599"},"PeriodicalIF":6.1000,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Surface & Coatings Technology","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0257897224012301","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, COATINGS & FILMS","Score":null,"Total":0}

引用次数: 0

Abstract

Cathodic deposition (CD) technology, as a surface treatment technology, is widely used to prepare surface protective layers of non-valve metals. However, due to the presence of a dense oxide film on the surface of valve metal, during the CD process, this dense oxide film will hinder the contact between ions in the electrolyte and the substrate surface, making CD deposition technology unsuitable for valve metal. In this paper, valve metal AZ31 Mg alloy was first treated by micro-arc oxidation (MAO) technology, and then CD treatment was performed using ethylene glycol organic solution as electrolyte. This method not only solves the problem that CD technology cannot be applied to valve metals and successfully prepares a coating with excellent friction and corrosion resistance, but also explores a new solution as a CD electrolyte. By comparing with the samples after CD treatment in deionized water solution and the samples after MAO, the results show that after CD treatment in deionized water solution, only the porosity (8.572 %) and coefficient of friction (COF) (0.403) of the coating were improved, but after CD treatment in ethylene glycol solution, the coating surface had the lowest porosity (4.263 %), the highest hardness (265.2 HV), and the smallest COF (0.362). Electrochemical tests further showed that the sample had the lowest corrosion current density (5.6099 × 10⁻¹⁰ A/cm²) after CD treatment in ethylene glycol electrolyte. The coating prepared by this method can be widely used in aerospace, medical equipment and other fields due to their excellent friction and corrosion resistance, and can increase the service life of Mg alloy parts. However, this method is currently more suitable for the processing of small parts. This study not only provides a valuable strategy for improving the performance of MAO coatings, but also provides a new direction for the application of CD technology on valve metals.

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

微弧氧化和阴极沉积改性AZ31镁合金表面性能研究

阴极沉积（CD）技术作为一种表面处理技术，被广泛应用于制备非阀门金属的表面保护层。然而，由于阀门金属表面存在致密的氧化膜，在CD过程中，这种致密的氧化膜会阻碍电解液中离子与衬底表面的接触，使得CD沉积技术不适用于阀门金属。本文首先采用微弧氧化（MAO）技术处理阀门金属AZ31镁合金，然后以乙二醇有机溶液为电解液进行CD处理。该方法不仅解决了CD技术无法应用于阀门金属的问题，成功制备了具有优异耐摩擦和耐腐蚀性能的涂层，而且探索了一种作为CD电解质的新解决方案。将去离子水中CD处理后的涂层与MAO处理后的涂层进行对比，结果表明：去离子水中CD处理后涂层的孔隙率（8.572%）和摩擦系数（COF）（0.403）得到改善，而在乙二醇溶液中CD处理后涂层表面孔隙率最低（4.263%），硬度最高（265.2 HV）， COF最小（0.362）。电化学测试进一步表明，在乙二醇电解质中CD处理后的样品具有最低的腐蚀电流密度（5.6099 × 10−10 A/cm2）。该方法制备的涂层由于具有优异的耐摩擦和耐腐蚀性能，可广泛应用于航空航天、医疗设备等领域，并可提高镁合金零件的使用寿命。但是，这种方法目前更适合小零件的加工。该研究不仅为提高MAO涂层的性能提供了有价值的策略，而且为CD技术在阀门金属上的应用提供了新的方向。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

Surface & Coatings Technology 工程技术-材料科学：膜

CiteScore

10.00

自引率

11.10%

发文量

921

审稿时长

19 days

期刊介绍： Surface and Coatings Technology is an international archival journal publishing scientific papers on significant developments in surface and interface engineering to modify and improve the surface properties of materials for protection in demanding contact conditions or aggressive environments, or for enhanced functional performance. Contributions range from original scientific articles concerned with fundamental and applied aspects of research or direct applications of metallic, inorganic, organic and composite coatings, to invited reviews of current technology in specific areas. Papers submitted to this journal are expected to be in line with the following aspects in processes, and properties/performance: A. Processes: Physical and chemical vapour deposition techniques, thermal and plasma spraying, surface modification by directed energy techniques such as ion, electron and laser beams, thermo-chemical treatment, wet chemical and electrochemical processes such as plating, sol-gel coating, anodization, plasma electrolytic oxidation, etc., but excluding painting. B. Properties/performance: friction performance, wear resistance (e.g., abrasion, erosion, fretting, etc), corrosion and oxidation resistance, thermal protection, diffusion resistance, hydrophilicity/hydrophobicity, and properties relevant to smart materials behaviour and enhanced multifunctional performance for environmental, energy and medical applications, but excluding device aspects.