等壁厚双层管半固态共挤压成形的数值模拟

Numerical simulation of thixo-co-extrusion for double-layer tube with equal wall thickness

通过ABAQUS软件模拟铝合金(A356)及镁合金(AZ91D)双层复合管的半固态反挤压触变成形过程。在内外层管壁厚相等的条件下,系统研究了温度场、应力场、流场、界面间接触力等在不同挤压速度下的分布规律。研究发现,随着挤压速度的增大,界面之间的接触力逐渐降低。当速度一定时,两坯料界面间的X向的接触力随着内部坯料镁合金比例的增加而增加,且此接触力和内外组合坯料的位置相关。模拟结果为优化复合管触变挤压工艺和模具设计提供重要依据。

The thixo-co-extrusion of the double-layer tube with equal wall thickness was investigated with A356 and AZ91D by finite element software ABAQUS.Under different extrusion velocities,the temperature fields,metal flow fields and the contacting forces in X direction between the interfaces were studied systematically.It is found that the contacting force can decrease with the increasing extrusion velocity.If the velocity is a constant,the force in X direction between the interfaces can increase with the increasing of the magnesium proportion,and the contact force is strongly influenced by the contacting inner and outer billets.The results have provided an important theoretical basis for improving the quality of the double-layer tube.