挤扭模通道倒圆角半径对铜合金塑性变形的影响  

Effect of round corner radius of twist extrusion die channel on plastic deformation of copper alloy

作　　者：李永志[1,2] 谢玉敏[1] 纪良波[1] LI Yong-zhi;XIE Yu-min;JI Liang-bo(School of Mechanical and Materials Engineering,Jiujiang University,Jiujiang 332005,China;School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]九江学院机械与材料工程学院,江西九江332005 [2]合肥工业大学材料科学与工程学院,安徽合肥230009

出　　处：《塑性工程学报》2020年第11期97-102,共6页Journal of Plasticity Engineering

基　　金：江西省自然科学基金资助项目(20151BAB206040);江西省教育厅科技项目(GJJ14722);九江学院科研项目(2015LGYB09)。

摘　　要：基于Deform-3D体积成形软件,对CDA110铜合金挤扭成形进行数值模拟,研究挤扭模通道横截面的不同倒圆角半径R值对坯料等效应变、挤扭力及模具应力的影响规律及变形均匀性;采用自行设计的倒圆角半径R=1.5 mm的模具,对该合金进行室温挤扭实验并与模拟结果进行对比分析。结果表明:R越小,挤扭力越大,模具应力分布越不均匀,挤扭剪切塑变能力越强;R越大,挤扭剪切塑变能力越差,但变形均匀性越好;优选倒圆角半径R值为1.0~1.5 mm时(挤扭模通道横截面尺寸10 mm×10 mm),可保证坯料挤扭强剪切塑性变形量,且挤扭力和模具应力显著降低。实验结果证实,合适的倒圆角半径R能确保材料整体细晶化,且不同区域材料硬度分布差距减小,变形均匀性增强。Based on Deform-3 D volume forming software,the twist extrusion forming of CDA110 copper alloy was simulated. The effect of different corner radii R of twist extrusion die channel cross section on the equivalent strain,the twist extrusion load and the stress of die were studied. A self-designed die with the corner radius R = 1. 5 mm was used to carry out the twist extrusion experiment of the alloy at room temperature and the experimental results were compared with the simulation ones. The results show that the smaller the R is,the greater the twist extrusion load is,the more uneven the stress distribution of the die is,and the stronger the twist extrusion shear plasticity is. The larger the R is,the worse the twist extrusion shear plasticity is,while the better the deformation uniformity is. When the radii of the rounded corner R are 1. 0-1. 5 mm( the cross section size of the twist extrusion die channel is 10 mm × 10 mm),the significant shear plastic deformation of billet is ensured,and the twist extrusion load and die stress are significantly reduced. The experimental results verify that the moderate corner radius R can make sure that the whole material is refined,and the distribution difference of hardness in different areas is reduced,and the deformation uniformity is enhanced.

关 键 词：挤扭变形 倒圆角半径 大塑性变形 模具应力 均匀系数 显微组织与硬度 

分 类 号：TG376.5[金属学及工艺—金属压力加工] TF124[冶金工程—粉末冶金]