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镁合金AZ91HP强流脉冲电子束表面处理及抗蚀性能研究 总被引:3,自引:0,他引:3
研究了强流脉冲电子束表面处理对镁合金AZ91HP腐蚀性能的影响。通过动电位极化曲线测定,处理样品在5%NaCl溶液中的抗蚀性能有显著改善。72h盐浸失重法测试中,处理样品的腐蚀速度最大可以降低一个数量级。扫描电镜(SEM)及电子探针(EPMA)分析发现,强流脉冲电子束轰击处理在AZ91HP样品表层引发快速熔凝过程,进而导致镁、铝元素的含量及分布形式发生变化。样品表面重熔层中Al元素的过饱和固溶及成分均匀化是改善其腐蚀性能的主要原因。 相似文献
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使用Nd-YAG激光器对AZ31镁合金板材表面进行了激光重熔处理,分析了激光重熔处理对其表面特性的影响.在激光扫描时,试样表面发生了快速熔凝,处理层可分为重熔区、热影响区两部分.重熔区的晶粒得到明显细化,硬度比基体提高5%.腐蚀试验表明,AZ31镁合金在激光重熔处理后,在3.5%的NaCl溶液中的耐蚀性得到明显改善.重熔区晶粒细化和Al元素富集是激光重熔表面处理提高其耐蚀性的主要因素. 相似文献
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HAO Sheng- zhi GAO Bo ZHOU Ji-yang DONG Chuang . State key laboratory for material modification by laser ion electron beams Dalian University of Technology Dalian China . Department of material engineering Dalian University of Technology Dalian China 《材料热处理学报》2004,25(5)
MAGNESIUM ALLOYS are now receiving more andmore applications in the electronic communication,aeronautic and automotive products due to their lowdensity,high strength to weight ratio and goodcastability[1-3]-However,the inherently poorcorrosion resistance of magnesium alloys limits theirfurther utilization.Therefore,significant efforts havebeing made to find one way that allows improving thecorrosion resistance of magnesium alloys effectively.Increasing the purity of magnesium alloy and t… 相似文献
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设计了AZ31镁合金的母材(BM)、搅拌摩擦焊接头(FSW)、焊后横向拉伸5%(FSW+T)和焊后拉伸加退火(FSW+T+A)等4组试样。通过对比4组试样在质量分数为3.5%的NaCl溶液中的耐腐蚀性能,探索焊后塑性变形对接头耐腐蚀性能的影响。结果发现,AZ31镁合金的耐腐蚀性能在搅拌摩擦焊接后显著改善,但焊后横向拉伸将显著降低接头的耐腐蚀性能,而拉伸后退火处理使接头耐腐蚀性能增强。4组试样的腐蚀速率由大到小为:BM>FSW+T>FSW≈FSW+T+A。焊后横向拉伸在AZ31镁合金焊接接头中引入拉伸孪晶及位错滑移,两者对接头的耐腐蚀性能产生不利影响,但位错滑移所起的作用更显著。 相似文献
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王芬 《特种铸造及有色合金》2011,31(12):1157-1159
采用有机镀膜的方法在AZ31镁合金表面制备了具有功能特性的有机薄膜.通过对循环伏安特性曲线的分析,研究了镁合金表面有机膜的生长机理.结果表明,有机膜的形成过程要经历形核、稳定生长和薄膜增厚3个阶段;结合盐雾腐蚀试验,分析了镁合金表面的耐腐蚀性能,探讨了有机镀膜的最佳工艺条件. 相似文献
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AZ31镁合金表面Al合金化层的制备与性能研究 总被引:1,自引:1,他引:1
为提高镁合金表面的耐蚀性,采用热喷涂技术在AZ31镁合金表面制备铝涂层,并利用脉冲钨极氩弧表面熔覆的方法进行表面重熔,获得富铝的合金化层,分析了合金化层的组织结构和性能。研究结果表明:在AZ31镁合金表面的铝合金化层中存在典型的树枝晶结构,含有金属间化合物Mg2Al3,Mg17Al12以及α-Mg和Al固溶体。显微硬度测试表明,铝合金化可使AZ31镁合金表面硬度由HV50左右提高到HV200左右。极化曲线测试表明,合金化层提高了镁合金表面的耐蚀性。 相似文献
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GAO Bo HAO Sheng-zhi ZOU Jian-xin JIANG Li-min ZHOU Ji-yang'''' DONG Chuang .State Key Lab. of Materials surface Modification by Laser Ion Electron Beams Dalian China .Department of Materials Engineering Dalian University of Technology Dalian China 《材料热处理学报》2004,25(5)
MAGNESIUM ALLOYS exhibit high strength toweight ratio and stiffness and are finding theirapplications in air,automobile and electronic industries.Despite the worldwide growing interests inmagnesium alloys,their inferior wear resistance is aserious impediment.Considering that wear is asurface-related behavior,surface modification canresolve the problem.Recently,intense and pulsed energetic beams areemerging as new and effective methods for surfacemodification.The High Current Pulsed Ele… 相似文献
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主要研究了挤压态AZ61镁合金在不同载荷和滑动摩擦速度条件下的磨损性能。采用SEM对磨损面进行显微组织观察与分析,讨论了不同载荷下材料的主要磨损形式。结果表明,磨损质量损失随着滑动摩擦速度和载荷的增加而增加。挤压态AZ61镁合金的磨损机制主要分为轻微磨损和严重磨损。轻微磨损主要是擦伤磨损、氧化磨损与剥层磨损,在磨损面上形成的擦痕与裂纹,其磨损程度较轻,磨损面积小;当载荷增加到100N和120N时,塑性变形和熔化在磨损面形成的磨痕较深且磨损面积大,表现为严重磨损。 相似文献
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利用静态失重法和金相观察研究了0.5%的Ce、0.2%的Ca、0.2%的Sr(质量分数)复合合金化对AZ91镁合金在质量分数为3.5%的NaCl水溶液中的腐蚀行为。结果表明,0.5%的Ce、0.2%的Ca、0.2%的Sr复合加入显著降低合金的腐蚀速率,其耐蚀性明显高于AZ91基体合金,也优于单独添加0.5%的Ce的合金。腐蚀性能提高的原因主要归结为:复合合金化导致α-Mg晶粒明显细化,Al元素的偏析减轻,块状的β-Mg17Al12相变为非连续网状分布。 相似文献
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Magnesium (Mg) alloys for metal electroplating require a surface pretreatment, i.e., the removal of the spontaneously oxidized surface layer (MgO, Mg(OH)2, and MgCO3). However, the use of highly toxic and/or corrosive acids in conventional pretreatment processes has become an issue. In this study, a facile and less toxic pretreatment is demonstrated and applied in aluminum (Al) electroplating. The immersion of the AZ31 Mg alloy into acetic anhydride (Ac2O) removed the spontaneously oxidized surface layer and formed a thin but stable magnesium acetate (Mg(OAc)2) layer that protects the metal substrate from further oxidation. The Al electroplating bath is a concentrated diglyme (G2)-AlCl3 organic solution that can readily dissolve Mg(OAc)2 to enable direct plating onto a metal substrate. The as-deposited Al layer has a compact and crack-free morphology that improves the corrosion resistance and hardness (2.7 GPa). Owing to the lack of an interfacial oxidized layer, heat treatment led to the successful diffusion of Mg and Al atoms, which increased the hardness to 4.4 GPa. The Ac2O pretreatment of Mg alloys enables the successful Al electroplating and subsequent heat treatment. 相似文献