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中国科学院大学学报 ›› 2008, Vol. 25 ›› Issue (2): 172-176.DOI: 10.7523/j.issn.2095-6134.2008.2.005

• 论文 • 上一篇    下一篇

高能气动喷丸致纯铜细晶化的实验与模拟

兰姣霞 王志甲 洪友士   

  1. 中国科学院力学研究所非线性力学国家重点实验室,北京100080
  • 收稿日期:1900-01-01 修回日期:1900-01-01 发布日期:2008-03-15

Experimentalinvestigationandfiniteelementsimulationongrain refinementofcopperduetoshotpeening

LANJiaoXiaWANGZhiJiaHONGYouShi   

  • Received:1900-01-01 Revised:1900-01-01 Published:2008-03-15

摘要: 高能气动喷丸是通过剧烈塑性变形产生细晶材料的方法之一.用纯铜作为实验材料在高能气动喷丸实验机上作喷丸实验,利用表面形貌仪、显微硬度仪以及电子背散射衍射方法对经喷丸处理的试样进行表面粗糙度、硬度及晶粒尺度的测量.结果表明,表面粗糙度随处理时间的增长呈指数衰减趋势;晶粒尺度细化了一个量级,由初始的25.48μm细化至252μm;且显微硬度由原来的058GPa增加到125GPa.量纲分析得到喷丸过程的5个无量纲参数,利用有限元模拟研究了无量纲参数的影响.自编制程序产生丸粒的随机碰撞并调用Ansys?lsdyna模拟碰撞过程,并将模拟1000次碰撞的结果与相应的实验值进行了比较.

关键词: 喷丸, 有限元模拟, 纯铜, 量纲分析, 剧烈塑性变形

Abstract: Abstract ShotPeening(SP)isatypicalsevereplasticdeformationmethodtoproduceultrafinegrainsofmetallic materials.Anexperimentalinvestigationiscarriedoutonpurecopperspecimensbymeansofashotpeening machinedrivenbyhighenergyairpressure,asurfaceroughnessmeasurmenttester,amicrohardnessindenter,an opticalmicroscopeandascanningelectronmicroscopeequippedwithelectricalbackscatterdiffractionapparatus.Theresultsshowedthatsurfaceroughnesstakesonanexponentialdecaywithdisposaltime,andthatthegrainsizeinthespecimenswith13333sis252micronscomparedwiththeoriginalvalueof2548microns,i.e.itis refinedbyoneorderofmagnitude.Themicrohardnesstestingonthespecimenshowedthehardnessincreasedfrom0.58GPato1.25GPaafterSPtreatment.Ontheotherhand,adimensionalanalysisisperformedtoexamineSP
processsothattoobtainfivedimensionlessparametersandthemethodoffiniteelementsimulationisusedtoanalyzetheeffectofdimensionlessparametersonsurfaceroughness.InordertofurtherunderstandSPprocess,weusedVB
towritethesubprogramfortherandomimpactsimulation,whichthenincorporatedwithfiniteelementcodeAnsys/ls-dynasoastosimulatethecollisionprocessbetweenballsandsample.Andsimulatedresultsandexperimental resultswerecomparedtoverifythefiniteelementmodel.

Key words: shotpeening, finiteelementsimulation, copper, dimensionalanalysis, severeplasticdeformation

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