无机材料学报 ›› 2013, Vol. 28 ›› Issue (8): 859-863.DOI: 10.3724/SP.J.1077.2013.12598 CSTR: 32189.14.SP.J.1077.2013.12598

• 研究论文 • 上一篇    下一篇

激光重熔改性铝合金微弧氧化膜层的组织与性能

喻 杰, 韦东波, 王 岩, 吕鹏翔, 狄士春   

  1. (哈尔滨工业大学 机电工程学院, 哈尔滨 150001)
  • 收稿日期:2012-10-09 修回日期:2012-11-05 出版日期:2013-08-20 网络出版日期:2013-07-15
  • 作者简介:喻 杰(1986-), 男, 博士研究生. E-mail: yujie163.ok@163.com

Structure and Property of Micro-arc Oxidation Coating Modified by Laser Melting and Solidifying on Aluminum Alloy

YU Jie, WEI Dong-Bo, WANG Yan, Lü Peng-Xiang, DI Shi-Chun   

  1. (School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China)
  • Received:2012-10-09 Revised:2012-11-05 Published:2013-08-20 Online:2013-07-15
  • About author:YU Jie. E-mail: yujie163.ok@163.com

摘要: 为了改善微弧氧化(MAO)膜层多孔疏松的组织和性能, 对其进行了激光重熔处理, 并制备了两种实验膜层: (1)选择双向电流脉冲和Na2SiO3-KOH体系的工作液, 在6082铝合金基体上制备平均厚度为18 μm的MAO膜层; (2)采用Nd:YAG激光器对上述MAO膜层进行激光重熔(LSM)处理, 获得MAO+LSM膜层。利用扫描电子显微镜(SEM)、X射线衍射仪、超显微硬度计和电化学分析仪分别检测上述两种膜层的微观形貌、相组成、表面硬度和耐蚀性能。结果表明: 激光重熔后的膜层由内往外分为致密层、中间层和重熔层, 组织致密、气孔率低的重熔层取代了MAO疏松层, MAO+LSM膜层中α-Al2O3相的比例得到提高, 硬度和耐蚀性能也进一步得到改善, 且保持了MAO膜层与基体的结合方式。

关键词: 铝合金, 微弧氧化, 激光重熔, 耐蚀性

Abstract: In order to improve performance and microstructure of micro-arc oxidation (MAO) coating, especially loose and porous characteristic, a laser melting and solidifying process (LSM) was introduced. Two kinds of samples were prepared: (1) MAO coatings, 18 μm average thickness, were produced on 6082 aluminum alloy by bipolar current pulse in Na2SiO3-KOH solution. (2) a melting process using a Nd:YAG laser was employed to modify above-mentioned MAO coatings to obtain MAO+LSM coating. Microstructure of two kinds of coatings (MAO coating and MAO+LSM coating) were examined by scanning electron microscopy. X-ray diffraction was used to determine the phase composition of the coatings. Coating hardness was tested by ultra-micro hardness tester, and corrosion performance was investigated by polarization test instrument. The results show that the MAO+LSM coating is composed of dense layer, intermediate layer and melting layer from inside to surface. The loose layer of MAO film is replaced by a dense and low porosity melting layer after LSM treatment. The occupancy of α-Al2O3 phase in MAO+LSM is improved compared with MAO coating. Hardness and anticorrosion performance of MAO+LSM coating are also further strengthened while the remelted coating keeps the same binding manner as MAO coating.

Key words: 6082 aluminum alloy, micro-arc oxidation, laser melting and solidifying, anticorrosion behavior

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