7050铝合金热挤压成形过程的有限元模拟

Finite element simulation on hot extrusion process of 7050 aluminum alloy

针对传统工程机械用销轴数量多、重量大、工况差等不足,以7050高强轻质铝合金代替传统钢质材料,采用DEFORM-3D有限元分析软件,对7050铝合金热挤压成形过程进行有限元数值模拟,分析了挤压载荷、金属流动速率、等效应变、等效应力和温度场等参量的变化规律。结果表明,销轴的热挤压变形过程可分为4个阶段,即挤压填充阶段、开始挤出阶段、稳定挤压阶段和终了挤压阶段;工件内部等效应变分布横向均匀性较好,除了尾部变形不均匀外,其他部位应变分布基本一致;在挤压凹模模口处形成死区,工件内部等效应力达到最大值。

Being in great quantity,heavy weight and poor working conditions in conventional engineering machinery,finite element method was used to simulate the deformation behavior of7050 aluminum alloy during hot extrusion process in order to verify if the aluminum alloy can replace conventional steel.Meanwhile,parameters like extrusion load,flow rate of metal particles,effective strain,effective stress and temperature field were analyzed.The results demonstrated that the hot extrusion process can be divided into four stages,i.e.upsetting and filling stage,extrusion start stage,stable extrusion stage and the end stage separately.Thedistribution of effective strain in the transverse direction is more homogeneous than that in the longitudinal direction,achieving almost good homogeneity in the billet except for the head part.At the hole of the extrusion die,dead zone is formed and the effective stress reaches the maximum value.