As an important engineering material, aluminum alloy profile is widely used in each department of national economy. With polyurethane mandrel in the hollow of the profiles, equal channel angular pressing (ECAP) can be used to refine mechanical properties of these hollow materials with good shape control effects. However, based on existing researches, the hollow profiles are only limited to circular ones. In this paper, a mechanical analysis of a square tube in ECAP with polyurethane mandrel is provided. Through the slab method in different deformation planes, the mechanical mechanism of shape control effects is found. The thicknesses can be maintained as its initial ones after ECAP. Both simulations and experiments are used to verify the calculated results by the analysis. After calculating, most errors between the final and initial thicknesses in both simulations and experiments are less than 10%.

铝合金型材作为一种重要的工程材料，在国民经济的各个部门得到了广泛的应用。在型材的空心中使用聚氨酯心轴时，可以使用等通道角挤压（ECAP）来改善这些空心材料的机械性能，并具有良好的形状控制效果。然而，基于现有研究，空心轮廓仅限于圆形轮廓。本文提供了带有聚氨酯芯棒的ECAP中方管的力学分析。通过在不同变形平面上的平板法，发现了形状控制效果的力学机理。厚度可以保持为ECAP之后的初始厚度。仿真和实验均用于通过分析验证计算结果。经过计算，