铜棒材连续挤压周向扩展成形力学模型  

Mechanical model of continuous extrusion circumferential expansion forming for copper bar

作　　者：田甜[1] 运新兵[1] 赵颖[1] 李冰[1] 伏洪旺 TIAN Tian;YUN Xin-bing;ZHAO Ying;LI Bing;FU Hong-wang(Engineering Research Center of Continuous Extrusion,Ministry of Education,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]大连交通大学连续挤压教育部工程研究中心,辽宁大连116028

出　　处：《塑性工程学报》2021年第8期175-181,共7页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51675074;51705062);辽宁省教育厅项目(JDL2019001);大连市科技创新基金资助项目(2018J11CY027)。

摘　　要：将铜棒材连续挤压周向扩展成形腔体分成3个变形区:扩展区、挤压区和成形区,利用主应力法推导出各分区单位挤压力公式,建立了腔体内的力学模型,并分析了扩展模扩展角、挤压模收缩角、流动通道长度和产品直径等工艺参数对单位挤压力的影响。结果表明:单位挤压力随挤压模收缩角和挤压模长度的增加而增加;扩展模扩展角为90°时,单位挤压力最小约为164.3 MPa,扩展模扩展角小于68°时,扩展模长度对单位挤压力的影响随着扩展模扩展角的增加逐渐减小,根据挡料块极限载荷确定了挤压模长度及可挤压产品直径的极限;最后通过工程试验对理论计算结果进行了验证。Chamber for continuous extrusion circumferential expansion forming of copper bar was divided into three deformation zones:extending zone,extrusion zone and forming zone.Unit extrusion force equation of each zone was derived by principal stress method and the mechanical model of chamber was established.The influence of process parameters such as extended angle of expansion die,extruded angle of extrusion die,flow channel length and product diameter on unit extrusion force was analyzed.The results show that the unit extrusion force increases with the increase of extruded angle of extrusion die and the length of extrusion die;when the extended angle of expansion die is 90°,the unit extrusion force is the smallest which is about 164.3 MPa.When the extended angle of expansion die is small than 68°,the influence of the length of extended die on the unit extrusion force gradually decreases with the increase of the extended angle of expansion die.The extrusion die length and the limit of squeezable product diameter were determined by the limit load of the abutment.Finally,the theoretical calculation results were verified by engineering tests.

关 键 词：铜棒材 连续挤压 周向扩展成形 力学模型 主应力法 

分 类 号：TG376[金属学及工艺—金属压力加工]