影响反向冷挤压凹模径向压力的因素研究

Influence Factors on Radial Stress of Backward Extrusion Die

基于Deform-3D数值模拟软件,通过单因素分析和正交试验方法,研究了各因素对反挤压凹模内壁径向压力的影响规律及程度大小。研究结果表明:以1060铝合金为例,变形程度由16%变化到81%,压力值由48MPa增加到872 MPa;高径比由0.4变化到1.2,其值增加70 MPa;摩擦因数由0.05变化到0.50,其值增加400 MPa;挤压速度对凹模内壁压力的影响很不明显,屈服应力与其的变化关系近似为线性。其中,挤压材料性能对内壁影响最大,高径比的影响最弱。最后,通过对1060铝合金进行物理模拟可知:各测点应变值的物理模拟与数值模拟结果,相对误差最大为13.30%,最小为0.38%。

With the single factor and orthogonal experimental method,Deform-3D was used to simulate the influence of each factors on radial stress of backward extrusion die.The results showed that the radial stress of 1060 aluminum alloy is increased from 48 to 872 MPa with deformation increasing from 16% to 81%.Its value is increased by 70 MPa with ratio of height to diameter ranging from 0.4 to 1.2,and 400 MPa with friction coefficient ranging from 0.05 to 0.50.Influence of extrusion speed on die stress is not obvious.The radial stress is linear relation to material yield stress.Meanwhile,the influence of extrusion material performance on radial stress is the largest,and the influence of ratio of height to diameter is least.Through physical simulation of 1060 aluminum alloy,the maximal relative error is 13.6% and minimum is 0.38% for the different maximum strains betweent physical and numerical simulation.