镁合金表面自纳米化研究进展及现状  

A Review on Surface Self-nanocrystallization of Magnesium Alloys

作　　者：王春明 杨牧南 黄建辉 刘位江 梁彤祥 WANG Chunming;YANG Munan;HUANG Jianhui;LIU Weijiang;LIANG Tongxiang(School of Materials Science and Engineering,Jiangxi University of Science and Technology,Ganzhou 341000)

机构地区：[1]江西理工大学材料科学与工程学院

出　　处：《材料导报》2019年第13期2260-2265,共6页Materials Reports

基　　金：江西理工大学博士启动基金(Jxxjbs17048);江西省教育厅科技计划项目(GJJ170548)~~

摘　　要：镁合金作为最轻的工程结构材料在航空航天、交通运输和电子通讯工业等领域均具有广泛的应用。镁合金的耐磨性和耐腐蚀性较差是限制其不能同铝合金一样被广泛应用的两个重要因素。因此,改善镁合金耐磨性和耐腐蚀性具有重大的意义,并受到了研究者的广泛关注。表面处理是提高镁合金耐磨性和耐腐蚀性的有效方法之一,其中,表面自纳米化技术存在以下两大优势:(1)组织沿厚度方向呈梯度变化,不会发生剥层和分离,无需考虑结合问题;(2)利用传统的表面机械处理或进行简单改进就可提高镁合金的耐磨性和耐腐蚀性,使其具有较大的开发应用潜力。目前,常用的镁合金表面自纳米化制备技术有表面机械研磨处理(SMAT)、激光喷丸(LSP)、超声喷丸(USP)、高能喷丸(HESP)、超音速微粒轰击等。表面机械研磨、高能超丸和超声喷丸技术的基本原理相似,而各自的振动频率不同。振动频率由大至小依次为超声喷丸、高能超丸、表面机械研磨。不同成分的镁合金表面处理后获得的纳米晶粒尺寸最小可达20 nm。另外,通过改进表面机械研磨设备开发的表面机械滚磨技术所得的纳米晶层的厚度可达100 μm。激光喷丸技术表面处理的镁合金纳米层厚度约为20 μm,纳米层晶粒尺寸可达20 nm。此外,经激光喷丸处理后镁合金表面的粗糙度小,使得合金具有更好的耐腐蚀性能。采用超音速微粒轰击技术处理的镁合金表面的纳米层晶粒的尺寸可达10 nm,其纳米层厚度大于使用激光喷丸技术处理的镁合金表面的纳米层。不论采用何种表面自纳米化技术,镁合金表面结构晶粒尺寸从表面向内部均可分为四个层次:表面纳米晶层、表面细晶层、粗晶应变层和无变化的镁基体。能量是影响纳米晶粒尺寸和纳米晶层的主要因素。同时镁合金表面纳米化后其硬度明显增大,有利于改善材料的�Magnesium (Mg) alloys are the lightest engineering structure materials widely used in aerospace, transportation and electronic communications, etc. The poor wear resistance and corrosion resistance of Mg alloys restrict directly its wide application. Therefore, it is of great significance to improve the wear resistance and corrosion resistance of Mg alloy. Surface treatment is one of the effective methods to improve the wear resistance and corrosion resistance of Mg alloys. Thereinto, surface nanocrystallization has great potential for development and application due to its two advantages:(1) the microstructures present a gradient change along the thickness direction, no peeling and separation are occurred, no interfaces are considered;(2) traditional surface mechanical treatment or simple improvement can be achieved. At present, surface nanocrystallization of Mg alloys used commonly includes surface mechanical attrition treatment (SMAT), laser shot peening (LSP), ultrasonic shot peening (UST), high energy shot peening (HESP), supersonic particle bombardment, etc. The basic principles of SMAT, HESP, UST are similar, the only difference is the vibration frequency. According to the vibration frequency from big to small, that is, UST, HESP, SMAT. Mg alloys with different composition after surface treatment obtain nanometer grain size as low as 20 nm. In addition, surface mechanical rolling technology (SMRT) is developed by refitting the SMA equipment. The thickness of nanolayer reaches 100 μm by SMRT. For LSP technology, the thickness of nanolayer is about 20 μm, the nanometer grain size reaches 20 nm. Furthermore, LSP has a better advantage in corrosion resistance due to the low surface roughness. The nanoscale grain of Mg alloys can reach up to 10 nm by supersonic particle bombardment technology. Meanwhile, the thickness of nanolayer is higher than that of LSP. No matter what surface nanocrystallization technology is used, the surface structure layer of Mg alloys can be divided into four layers from the surface

关 键 词：镁合金 表面自纳米化 力学性能 腐蚀行为 

分 类 号：TG17[金属学及工艺—金属表面处理]