摘要
分析了铜壳零件加工工艺,拟定了加工方案。以反挤压工序为例,提出了一种新的扭转颤振复合挤压方法。基于有限元分析软件Deform-3D分别建立了传统挤压、轴向振动辅助挤压以及扭转颤振复合挤压有限元模型。分析了不同加载方式下,冲头旋转挤压速度、凹模振动速度与成形载荷的关系,探讨了镦粗区、环形区和挤压筒区的金属流动规律和速度分布,应变变化规律和应变分布。结果表明:与传统挤压相比,轴向振动辅助挤压和扭转颤振复合挤压能降低平均成形载荷,且成形载荷呈振荡式变化,振荡频率与施振频率相同;扭转颤振复合挤压的最大成形载荷较轴向振动辅助挤压降低约10%。扭转颤振复合挤压的金属流动速度最快,速度间断线位于镦粗区和环形区中部,环形区金属流转角最小,金属流动更顺畅、平稳,可以有效减少折叠和空洞等缺陷,提高成形件性能。扭转颤振复合挤压变形死区范围最小,过渡区范围最大;在成形后期,变形死区消失,镦粗区和环形区应变分布趋向均匀。
The processing technology of copper shell parts was analyzed, and the processing scheme was laid out. Taking the reverse extrusion process as an example, a new extrusion method combined with torsion and flutter was proposed. Based on the finite element analysis software Deform-3 D, the finite element models of traditional extrusion, axial vibration-assisted extrusion and extrusion combined with torsion and flutter were established, respectively. The relationship between rotating extrusion speed of punch, vibration speed of die and forming load under different loading modes was analyzed. The metal flow law and velocity distribution, strain variation law and strain distribution in upsetting zone, annular zone and extrusion cylinder zone were discussed. The results show that compared with traditional extrusion, axial vibration-assisted extrusion and extrusion combined with torsion and flutter can reduce the average forming load, and the forming load changes in an oscillatory manner, and the oscillation frequency is the same as the vibration frequency;the maximum forming load of extrusion combined with torsion and flutter is about 10% lower than that of axial vibration-assisted extrusion. The metal flow velocity of extrusion combined with torsion and flutter is the fastest, and the velocity discontinuity line is located in the middle of upsetting zone and annular zone. The metal flow angle in annular zone is the smallest, and the metal flow is smoother and more stable, which can effectively reduce the defects such as folding and cavity and improve the performance of the formed parts. The range of deformation dead zone in extrusion combined with torsion and flutter is the smallest, and the range of transition zone is the largest;in the later stage of forming, the deformation dead zone disappears and the strain distribution in upsetting zone and annular zone tends to be uniform.
作者
孙克锐
徐海利
杨庆华
SUN Ke-rui;XU Hai-li;YANG Qing-hua(College of Mechanical and Electrical Engineering,Zhejiang Tongji Vocational College of Science and Technology,Hangzhou 311231,China;Hangzhou Yihui Technology Co.,Ltd.,Hangzhou 311121,China;Key Laboratory of Special Purpose Equipment and Advanced Mac*hining Technology,Ministry of Education&Zhejiang Province,Zhejiang University of Technology,Hangzhou 310023,China)
出处
《塑性工程学报》
CAS
CSCD
北大核心
2021年第12期36-43,共8页
Journal of Plasticity Engineering
基金
浙江省教育厅一般科研项目(Y201942873)。
关键词
振动辅助挤压
扭转颤振复合挤压
有限元模拟
成形载荷
vibration-assisted extrusion
extrusion combined with torsion and flutter
finite element simulation
forming load
