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摘要：
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以304奥氏体不锈钢作为挤压材料,利用有限元法对ECAP(等径角挤压)模具结构进行了优化分析,并就模具拐角圆弧的圆心位置参数X=0,5,10,20 mm时,对挤压后材料所获的等效应变量的大小及均匀性进行了模拟分析。结果发现,在拐角圆弧角度一定时,X=0时材料获得的等效应变值最大,变形均匀性最好。实际挤压实验结果表明,当X=0时,材料内部所受等效应变量的大小及均匀性与模拟结果一致。挤压后试样金相组织出现织构,沿某一方向晶粒明显被拉长,而在其垂直方向明显被挤压变细,在变形区内试样变形均匀。
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The structure of Equal Channel Angular Processing(ECAP) die was optimized by using Finite Element Analysis(FEA) where 304 austenitic stainless steel was adopted as the analyzing object.Equivalent strain and uniformity of the deformation of extruded stainless steel were simulated and analyzed when the center location parameter X equaled 0,5,10,20mm respectively.The results of FEA simulations indicate that when X=0 and the die corner angle keeps constant,the equivalent strain is biggest and uniformity of deformation obtained is best.The results of actual extrusion experiment show that the equivalent strain and uniformity of deformation obtained are accordant with that of FEA simulations.The orientation textures,where grains are evidently elongated along a orientation,however compressed and refined in the perpendicual one,appear in the optical microstructure of the sample after extrusion.The deformation textures of the sample appear homogenous in the deformation zone.
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基金项目：
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国家自然科学基金资助项目(50871041)
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作者简介：
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参考文献：
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