摘要:
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对等通道转角挤压Mg-Li合金进行了有限元分析和实验研究。模拟结果表明:随着挤压速度或摩擦的增大,试样整体变形越来越不均匀。实验结果表明:随着挤压速度的增大且无润滑的情况下,试样沿轴线方向出现了与剪切平面相平行的鱼鳞状裂纹;在挤压速度较低且胶体石墨润滑的情况下,试样表面光滑,无裂纹产生;经ECAE一道次挤压,实验合金中α相的晶粒大小由20μm左右变为10μm左右。
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Equal channel angular extrusion of Mg-Li alloy was investigated by finite element method and experiment method.The simulation result shows that deformation of the whole sample is heterogeneous when the extruding speed or the friction coefficient becomes larger gradually.Experimental result shows that increasing the extruding speed without lubricant,the shape of surface crack of fish scale type is found along the axial direction paralleled to the shear plane.The surface of sample lubricated with colloidal graphite is smooth and no crack appeared.The grain size of α phase in the Mg-Li alloy is reduced to 10 μm from 20 μm.
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基金项目:
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内蒙古自治区自然科学基金资助项目(200408020707);;
内蒙古自治区高等学校科学研究项目(200705046)
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作者简介:
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参考文献:
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[1]Yamashita A,Horita Z,Langdon T G.Improving the me-chanical properities of magnesium and magnesium alloy throngsevere plastic deformation[J].Mater.Sci.Eng.A,2001,(300):142-147.
[2]Segal V M.Materials processing by simple shear[J].Ma-ter.Sci.Eng.A,1995,(197):157-164.
[3]曹富荣.超轻镁合金的制备和高温变形机理的研究[D].沈阳:东北大学,1999.
[4]乐启帜,崔建忠,李红斌,等.Mg-Li合金研究最新进展及其应用[J].材料导报,2003,12(17):1-5.
[5]Tanno O,Obuchi K.Effect of rare-earth elements on thestrictures and mechanical properties of Mg-8%Li alloys[J].Journal of Japanese Institute of Light Metals,1992,2(1):3-8.
[6]Kim S H.Effects of rare earth(Y,Nd)on the corrosion be-haviors of Mg-Li-Al light alloys[J].J.Corros Sci.Soc.Korea,1997,26(3):160-165.
[7]Iwahashi Y,Wang J,Horita Z,et al.Principle of equal-channel angular pressing for the processing of ultra-finegrained materials[J].Scripta Metar.,1996,35(2):143-146.
[8]Yoon S C,Quang P,Hong S I,et al.Die design for homoge-nous plastic deformation during equal channel angular pressing[J].Journal of Materials Processing Technology,2007,(187-188):46-50.
[9]Semiatina S L,DeLob D P.Equal channel angular extrusionof difficult-to-works alloys[J].Materials and Design,2000,(21):311-322.
[10]Yang Yi-lang,Shyong Lee.Finite element analysis of strainconditions after equal channel angular extrusion[J].Journalof Materials Processing Technology,2003,(140):583-587.
[11]Zairi F,Aour B,Gloaguen J M,et al.Numerical modellingof elastic-viscoplastic equal channel angular extrusion processof a polymer[J].Computational Materials Science,2006,(38):202-216.
[12]吴炬,向国权,程先华.模具外接圆弧角对纯铝ECAE影响的有限元分析[J].上海交通大学学报,2005,39(7):1063-1065.
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