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摘要：
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异型钢管拉拔成形是一种高质量、高效率和低消耗的管材成形加工工艺。以十字形钢管为研究对象,采用有限元技术对拉拔成形过程进行数值模拟,得到了成形过程中管料的变形规律。研究发现:在应力分布上,轴向、周向和径向应力随管料在模具中位移增加而增大,三者最大值均出现在减径带与定径带连接处;沿壁厚方向,中心层应力分布较均匀。在应变分布上,塑性变形主要发生在管料与模具初始接触处及减径带与定径带连接处,周向应变沿拉拔轴向分布有较大变化,在模具入口端部分数值为负,在出口端部分数值为正。同时,模拟讨论了周向压缩系数η、拉拔速度v和摩擦系数μ对拉拔过程的影响,当η在1.05~1.14之间变化时,拉拔过程较稳定,应力应变曲线分布平稳;拉拔应力随着μ的增加而增大;当v=250mm/s时,拉拔应力取得最小值。
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Profiled steel tube drawing process is an advanced forming process for manufacturing tubes with high quality,high efficiency,and low consumption.Based on FEM,the cross tube drawing process is simulated and the forming laws are obtained.The results show that,axial stress,circumferential stress and radial stress increase with an increase of tube's axial displacement in the die and the maximums of them all appear at the joint between reducing straight and calibrating straight.Along the wall thickness direction,stress distributions in central layer are smoother than that in exterior surface and inner surface.The plastic deformation mainly occurs at the initial contact zone and the joint mentioned above.There is a wider change of circumferential strain distribution along the drawing axial direction,that is,the strain is positive at the entrance of die and negative at the exit.Meanwhile,the effect of some factors to drawing process,such as circumferential compression coefficient η,drawing velocity v and friction coefficient μ is investigated.When η ranges from 1.05 to 1.14,the drawing process is stable,and there is no rapid change in stress-strain distribution;The larger the value of μ,the larger the drawing stress;When v equals to 250mm/s,the drawing stress reaches the minimum.
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作者简介：
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参考文献：
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