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摘要：
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成形性是金属成形中材料最重要的性能之一。研究表明,高速下成形性有较大提高。本文综述了国外关于成形性的影响因素的研究现状,总结了高速率下成形性得到提高的主要原因:惯性是影响高速率成形性的主要因素,它有助于分散变形,抑制变形集中化;并对高速率下缩颈模式有很大影响,惯性力导致产生多处缩颈,并抑制缩颈集中化;高速的模具冲击作用同样是一个重要的影响因素,其产生惯性减薄挤压作用,从而使工件受到压缩应力而减少损伤参数,达到稳定变形的效果;应变速率的增加可能引起材料本构关系的改变,从而增加材料成形性。
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Formability may be the most important material property in metal forming.It was reported that the formability of some materials was improved dramatically at high velocities.The main purpose of this paper was to review the studies in the literatures about the factors influencing materials formability of sheet metals under high rate forming conditions.Some main effects were summarized,such as inertial,die impact and changes in constitutive behavior.Inertial was the dominating factor influencing high velocity formability.It acted to diffuse deformation and prevent localization,also responsible for the different necking pattern due to its resulting in multiple necking and preventing localized necking.High velocity impact was also a strong factor and had a stabilizing influence through inertial ironing and reduction in damage parameters due to compressive stresses.High strain rate might induce changes in constitutive behavior,which contributes to improve formability.
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基金项目：
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国家自然科学基金资助项目(50375114);;
塑性成形模拟及模具技术国家重点实验室资助项目(05-03)
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作者简介：
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参考文献：
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