基于DEFORM-3D的弹体精密挤压工艺

Precision extrusion process for projectile body based on DEFORM-3D

利用有限元模拟软件DEFORM-3D对某Φ215 mm口径弹体的精密挤压成形工艺进行研究。分析了弹体成形过程中大长径比、变截面等工艺难点,计算了弹体断面收缩率,明确了可采用精密挤压工艺成形该弹体;设计了精密挤压成形的工艺模具,并且为降低成形载荷,对凸模和凹模的尺寸进行了优化分析;通过设置弹体壁厚为6、7和8 mm共3组实验,获得了不同壁厚金属坯料的流动速度场、温度场和等效应变场的分布特征以及成形载荷的变化规律。结果显示,成形载荷随着壁厚的增大而减小,其中壁厚为7 mm的金属坯料成形过程中的温度分布和金属变形均较为均匀,其为最优壁厚。壁厚为7 mm的金属坯料的成形载荷为84.0 MN,应选择公称压力为90.0 MN的设备进行试制。

The precision extrusion forming process of aΦ215 mm caliber projectile body was studied by finite element simulation software DEFORM-3D.Then,the process difficulties of large aspect ratio and variable cross-section during the projectile body forming process were analyzed,and the cross-sectional shrinkage rate of projectile body was calculated.It was clear that the projectile body could be formed by the precision extrusion process.Furthermore,the precision extrusion forming process mold was designed,and the dimensions of punch and die were optimized and analyzed to reduce the forming load.By setting three sets of experiments with the wall thicknesses of 6,7 and 8 mm for projectile body,respectively,the distribution characteristics of flow velocity field and temperature field and equivalent strain field,and the changing rules of forming load for metal billets with different wall thicknesses were obtained.The results show that the forming load decreases with the increasing of wall thickness,and the temperature distribution and metal deformation during the forming process of the metal billet with the wall thickness of 7 mm are relatively uniform,which is the optimal wall thickness.The forming load of the metal billet with the wall thickness of 7 mm is 84.0 MN,and the equipment with the nominal pressure of 90.0 MN should be selected for the trial production.