Study Of Pure Copper Wires And Copper-iron Composites With High Strength And High Conductivity

High-strength and high-conductivity pure copper wires and Cu-Fe in situcomposites were produced by cryogenic deformation and thermo-mechanicalprocessing respectively.The structures were investigated by Scanning electronmicroscope (SEM),Transmission electron microscope (TEM),High resolutiontransmission electron microscope (HRTEM),Optical microscope (OM) and X-raydiffraction(XRD).Besides measuring the tensile and electric performances byCSS-1101 all-purpose electro-test-machine and 7081 numeric pressure meterapart,we also evaluated the thermal stability and anti-atmospheric corrosionperformance of Cu-Fe in situ composites.The results showed that the strcucture of cryogenic deformated copper was morecompact compared with that of room temperature deformated copper;the vastmajority of the matrix grains were kept in the nanocrystalline/ultrafine grain regimewhile the others(at a volume fraction of 25%)were sufficiently large after appropriaterecrystallization anneal;the ultimate tensile strength of cryogenic deformated copperwas much higher,but conductance was lower a little.It was concluded that purecopper could gain excellent and compositive performances by means of reasonablerecrystallization anneal following heavily cryogenic deformation.With regard to Cu-Fe in situ composites,nano-grains came into being whendisformation was finished;the ultimate tensile strength and resistance modulus allrose with the increase of drawing strain,fell after intermediate heat treatment andwent up in the succedent deformation;they had good thermal stability andanti-atmospheric corrosion performances.It was concluded that people could obtainthe expected combination of better strength and conductivity for the composite bycold drawing and intermediate heat treatment.