强流脉冲离子束辐照镁合金微弧氧化膜致密化机理.doc

文档介绍：
强流脉冲离子束辐照镁合金微弧氧化膜致
密化机理#
韩晓光*
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(大连海事大学交通运输装备与海洋工程学院,大连,116023)
摘要:采用强流脉冲离子束在束流密度为 200A/cm2,辐照次数分别 1-10 次条件下对镁合金
微弧氧化膜进行改性处理。采用扫描电子显微镜对辐照后镁合金微弧氧化膜的表面和截面形
貌进行观察,在辐照次数为 5 次条件下获得连续致密化改性层。通过对氧化膜表面的温度场
和应力场计算得出了强流脉冲离子束辐照氧化膜产生的热力学效应是氧化膜冲击加工致密
化的根本原因。
关键词:强流脉冲离子束,镁合金,微弧氧化,冲击加工
中图分类号:
The mechanism for densification of MAO films irradiated
by high-intensity pulsed ion beam
HAN Xiaoguang
(Transportation Equipments and Ocean Engineering College, Dalian Maritime University,
Dalian,116023, China)
Abstract: Abstract: Microarc oxidation (MAO) film on AZ31 magnesium alloy was modified by
high-intensity pulsed ion beam(HIPIB) at the ion current density of 200A/cm2 with 1-10 shots. a
continuous pact remelted layer was obtained on the surface of MAO film with 5 shots.
The surface and cross sectional morphologies of the irradiated MAO films were observed by using
scanning electron microscopy. It is found that the shock waves produce by HIPIB irradiation were
in charge of the densification of MAO film.
Key words: High-intensity pulsed ion beam; Magnesium alloy; Microarc oxidation; shocking
process
0 引言
镁合金是目前工业上可应用的最轻金属结构材料,因其比强度高、减振性好、电磁屏蔽
能力强、易加工、可再生利用而被誉为“21 世纪绿色工程金属结构材料”。然而镁合金的耐
蚀性能差严重制约了其工业化进程。为了改善镁合金的耐蚀性能,多种表面改性技术被应用
于对镁合金进行表面处理。比较常用的方法包括化学转化膜[1]、阳极氧化[2-4]、离子注入
[5-6]、激光表面处理[7-8]、微弧氧化[9-12]等,其中微弧氧化技术能够在 Al、Mg、Ti、Nd
等阀金属表面原