Research On Continuous Cold Drawing Process And Microstructure And Properties Of Copper Wire

Horizontal continuous casting TP2 copper wire with good thermal conductivity,electrical conductivity and corrosion resistance,used as the cable,bonding wire,contact line in the network information,communications,railway and electric and other industries.At present,with the development of various products to the miniaturization,high precision,the quality and performance of copper wire is also payed more and more attention,the industry of China’s copper wire goes into the stage of precision and efficiency.In this paper,the research focused on the drawing process of horizontal continuous casting copper wire,the change of the structure and performance of the wire breaking process,and the phenomenon of wire breaking were studied in this paper.In this paper,the horizontal continuous casting and drawing process of copper wire material were analyzed,and the stress conditions of drawing die and copper wire were analyzed,which layed the foundation for the improvement of production process.The composition,electrical conductivity and thermal conductivity of the copper wire were analyzed.The content of Cu is 99.979%,the content of P is 0.017%,the oxygen content is 0.00029%,heat conduction rate is K /61.3(7)?(28)kcmW(8),after drawing,the electrical conductivity of copper wire is stable at 97%IACS.The microstructure and properties of copper wire in the drawing process were analyzed,and the change of the structure was divided into 3 steps:At first,the local slip,the grain began to split;Then the grain deformation is increased,the twins were formed,the grain boundary became blurred,fiber stripe appears;The final grain boundary disappears,the formation of fibrous tissue.In the continuous cold drawing process of copper wire,with the increase of true strain,the hardness of the copper wire was increased gradually,Vickers-hardness eventually reached 120 HV,the nano-indentation hardness reached 1.5GPa,the elastic modulus was also increased by nearly 4%,reaching 127.2GPa;The tensile strength was gradually increasing and increasing rate from big to small,the final stability in 450 MPa,while the extension rate is gradually reduced,and ultimately less than 5%.Research and Analysis on the breaking line of copper wire drawing process,explore the reasons for the breaking of the wire from the aspects of drawing billet,drawing ring,drawing die,drawing lubricant.So the paper puts forward the technology improvementmeasures,reduces the occurrence of the phenomenon of the disconnection,and improves the processing efficiency.