中文摘要：

采用基于任意拉格朗日—欧拉（Arbitrary Largrang-Euler,ALE）算法的HyperXtrude软件模拟带有细小特征的薄壁空心铝型材挤压过程,以模孔出口处材料流速均方差作为衡量其均匀性的指标,通过设计一系列阻流块有效控制材料流速及型材变形。研究阻流块对流速均匀性的影响规律,提出阻流块设计的一般原则。结果表明,阻流块的截面形状对流速控制起着关键作用,应保证阻流块截面形状合理,再调整阻流块高度及其到模孔的距离,可有效控制材料流速及型材的变形,获得形状和尺寸符合要求的型材。在阻流块高度的一定范围内,增加其高度可增加型材整个截面上材料流速的均匀性,但阻流块的宽度对平衡材料流速作用不大。

英文摘要：

The extrusion process of a thin-walled hollow aluminum alloy profile with small features is simulated by using arbitrary Largrang-Euler（ALE） algorithm based HyperXtrude software. The material flow velocity standard deviation in the exit of the die hole is used as a criterion to evaluate velocity uniformity. By designing a series of baffle-blocks, the material flow velocity and the deformation of extrudate are controlled effectively. Effect of baffle-blocks on velocity uniformity is analyzed and a design method of baffle-blocks is proposed. The simulation results demonstrate that the section shapes of baffle-blocks play a key role in controlling material flow velocity in exit. When baffle-blocks have a reasonable section shape, material flow velocity and the deformation of extrudate can be controlled effectively and qualified profiles can be gained by adjusting height and distance between baffle-blocks and mold hole. In a certain range of the baffle-block＇s height, the increase of the height of baffle-block can increase the uniformity of the materials flow velocity effectively. However, the increase of the width of baffle-blocks may not work on the balance of material flow material.