蝶形模具挤压过程的数值模拟

Numerical simulation of butterfly die extrusion process

在Simufact9.0软件平台上,采用基于Euler网格描述的有限体积法,对蝶形模具非稳态挤压过程进行数值模拟,并与传统模具进行对比。数值模拟结果表明:当采用蝶形模具挤压方型管材时,金属的流动及变形较传统模具挤压时的更加均匀,分流桥上端及焊合室的死区减小;挤压力曲线平稳,没有明显的突变,突破分流孔的挤压力较传统模的降低约72.2%,最大挤压力降低约17.3%;模具的等效应力分布更加均匀,最大等效应力降低约11.2%,模具的使用寿命提高,且分流桥的弹性变形减小,模芯的稳定性提高。

Based on Simufact9.0 commercial software the non-steady state extrusion process of butterfly die was investigated using finite volume method（FVM） of Euler mesh description and compared with the traditional porthole die extrusion.The simulation results show that when the square tube profile is extruded using the butterfly die,the metal flow and deformation are more homogeneous than those of the traditional die,and the dead metal zone at the top of dividing bridge and welding chamber decreases.Furthermore,the extrusion load curve is smoother and there is no obvious mutation change.The breaking portholes load and the maximum extrusion load of the butterfly die are reduced by 72.2% and 17.3%,respectively.The effective stress distribution is more uniform,and the maximum effective stress is reduced by 11.2%,which improves the die operating life.Moreover,the elastic deformation of the dividing bridge is lowered,and the stability of the die core is improved.