为便于取出微正挤压零件,设计了具有分瓣式结构的微正挤压凹模,并成功成形出最小挤出杆直径为0.25 mm的微正挤压件.采用扫描电子显微镜(SEM)及金相显微镜对微正挤压件的表面形貌及微观组织进行了观察.结果表明,随着挤出杆尺寸的减小或晶粒尺寸的增大,内外层材料的非均匀塑性变形程度增加;当挤出杆尺寸降低到亚毫米尺度时,微挤压成形件发生了一定弯曲;微正挤压件纵向和横向微观组织的非均匀分布表明,在微正挤压成形过程中材料在纵向和横向上都经历了严重的非均匀塑性变形.材料的非均匀塑性变形程度是随着挤出杆尺寸的减小或晶粒尺寸的增加而不断增加的.
参考文献
| [1] | M. Geiger;M. Kleiner;R. Eckstein;N. Tiesler;U. Engel .Microforming[J].CIRP Annals,2001(2):445-462. |
| [2] | QIN Y.Micro-manufacturing engineering and technology[M].UK:Elsevier Inc,2010 |
| [3] | U. Engel;R. Eckstein .Microforming-from basic research to its realization[J].Journal of Materials Processing Technology,2002(0):35-44. |
| [4] | Yasunori Saotome;Hiroyuki Iwazaki .Superplastic backward microextrusion of microparts for micro-electro-mechanical systems[J].Journal of Materials Processing Technology,2001(1/3):307-311. |
| [5] | SAOTOME Y;IWAZAKI H.Superplastic extrusion of microgear shaft with photochemically machinable glass dies[C]//[A].Berlin:Ddp Goldenbogen Sigurd Goldenbogen,2000:982-982. |
| [6] | SAOTOME Y;ITOH A;AMADA S.Superplastic micro forming of double gear for milli-machines[C]//[A].北京:万国学术出版社,1993:2000-2005. |
| [7] | Y. Saotome;H. Iwazaki .Superplastic extrusion of microgear shaft of 10 μm in module[J].Microsystem technologies,2000(4):126-129. |
| [8] | EICHENHUELLER B;EGERER E;ENGEL U .Microforming at elevated temperature-forming and material behavior[J].International Journal Advanced Manufacturing Technology,2007,33:119-124. |
| [9] | W. J. Kim;Y. K. Sa .Micro-Extrusion of ECAP Processed Magnesium Alloy for Production of High Strength Magnesium Micro-Gears[J].Scripta materialia,2006(7):1391-1395. |
| [10] | CAO J;KRISHNAN N;WANG Z et al.Microforming:experimental investigation of the extrusion process for micropins and its numerical simulation using RKEM[J].Journal of Manufacturing Science and Engineering,2004,126:642-652. |
| [11] | KRISHNAN N;CAO J;DOHAD K .Study of the size effects and friction conditions in microextrusion-part Ⅰ:microextrusion experiments and analysis[J].Journal of Manufacturing Science and Engineering,2007,129:669-676. |
| [12] | Sunal Ahmet Parasiz;Brad Kinsey;Neil Krishnan;Jian Cao;Ming Li .Investigation of Deformation Size Effects During Microextrusion[J].Journal of manufacturing science and engineering,2007(4):690-697. |
| [13] | W.L Chan;M.W. Fu;J. Lu .Experimental and simulation study of deformation behavior in micro-compound extrusion process[J].Materials & design,2011(2):525-534. |
| [14] | W.L. Chan;M.W. Fu;B. Yang .Study of size effect in micro-extrusion process of pure copper[J].Materials & design,2011(7):3772-3782. |
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