U形板件模压各区应变演化规律研究

目的 探究U形件模压的应变演化规律，为U形件大塑性变形提升材料性能提供理论指导。方法 基于有限元仿真软件DEFORM对U形件进行了限制性模压仿真研究，分析了应变分布规律并对其进行了量化的讨论。结果 试样经过单道次挤压后，直齿区域应变呈现波动式分布，受到剪切作用的位置均呈现中心处应变较大并向两侧逐渐减小，在靠近齿拐角的区域应变最小。扇形齿区域应变分布规律为齿面跨度越小，应变越大，齿面跨度越大，应变越小。从两道次模压变形来看，随着变形道次的增加，整体应变显著增加。应变分布曲线的波动程度随着变形道次的增加有所降低，应变均匀性有所改善。结论 通过对直齿、扇形齿及其多道次的应变演化规律来看，减小齿宽及增加变形道次有助于累积应变。

Strain Evolution Law of Different Region of U-shape Plate Groove Pressing

The paper aims to understand the strain evolution law of U-shape plate groove pressing and provide theoretical guidance for severe plastic deformation of U-shape plate to improve the material performance. Finite element simulation of U-shape groove pressing was carried to analyze the strain distribution and quantitative evolution during the process based on the commercial software DEFORM. The results showed that the strain of straight groove region fluctuated and up to the top in the center following gradually decrease to both sides and reached the smallest in the region near the corner of the groove after first pass. The strain distribution rule of the fan groove region was that the smaller the groove surface span was, the larger the strain was. The larger than groove surface span was, the smaller the strain was. From the perspective of two passes of compression deformation, the overall strain increased significantly with the increase of passes. The degree of fluctuation of the strain distribution curve decreased as the number of deformation passes increased. And the strain uniformity was improved. According to the law of strain evolution of straight grooves, fan-shaped grooves and multi-pass, reducing the groove width and increasing the deformation passes contribute to the accumulation of strain.