Study on deformation characteristics of multi-pass continuous drawing of micro copper wire based on crystal plasticity finite element method

Abstract Copper-based wire has excellent comprehensive performance and is widely used in integrated circuit packaging, electronic communication, connectors, audio and video transmission, and other fields. Based on the crystal plasticity finite element method, the crystal plasticity finite element model of multi-pass continuous drawing deformation of pure copper micro wires was established, and the reliability of the model was proved. The continuous drawing deformation behavior of micro wires under high-speed deformation and micro wire diameter scale effect was studied. The research shows that there is a fracture risk zone under the alternating action of positive and negative stress values in the deformation zone of the drawn wire. The changing drawing force and contact stress during the continuous drawing process of the wire will also reduce the stability and surface quality of the wire during the drawing process. The shear deformation and slip degree of the surface grain of the drawn wire are greater than those of the core grain, and the drawing die has a greater impact on the slip system state of the surface of the wire. With the increase in drawing passes, the mechanical characteristics inside the wire increase accordingly, and the deformation uniformity inside the grains is improved. The established model can demonstrate the deformation history characteristics and structure inheritance of the continuous wire drawing process.