铜钛复合管绕弯成形基、覆管的耦合作用

Coupling effect of base tube and covered tube of copper-titanium composite tube in rotary-draw bending process

为了揭示铜钛复合管绕弯成形过程中的基、覆管的耦合作用及变形机理,建立了单层钛管、单层铜管和铜钛双金属复合管绕弯—回弹全过程有限元模型,从回弹和截面变形的预测上验证了有限元模型的可靠性。基于所建有限元模型,通过分析、对比模拟结果发现:覆管、基管在绕弯过程中相互作用力较小,不存在明显的变形不协调现象;复合管的回弹量介于钛、铜管之间,是覆管与基管共同回弹的结果;绕弯过程中,基管降低了覆管的截面变形量,而覆管增大了基管的截面变形量,覆管和基管的相互作用在整体上减缓了复合管的截面变形。

To reveal the coupling and deformation mechanism of the base tube and the covered tube of copper-titanium composite tube during the rotary-draw bending forming process,the finite element(FE)models of whole rotary-draw bending-springback process were established for the single-layer titanium tube,single-layer copper tube and copper-titanium bimetal composite tube.The reliability of the FE model was verified from the prediction of springback and section deformation.Based on the established FE models,it is found by analyzing and comparing the simulation results that the interaction force between the covered tube and the base tube is small in the rotary-draw bending process,and there is no obvious deformation incoordination phenomenon;the springback amount of composite tube is between those of titanium tube and copper tube,which is the result of the joint springback of the covered tube and the base tube;the base tube decreases the section deformation amount of the covered tube in the rotary-draw bending process,while the covered tube increases the section deformation amount of the base tube.The interaction between the covered tube and the base tube reduces the section deformation of the composite tube overall.