The Influence Mechanism Of Deep Cryogenic Treatment On The Microstructure And Electrical Conductivity Of Cu Alloys

Research cryogenic treatment began in the fifties and sixties, at first mainly usedin cutting tools, molds, bearings and other parts of the. After cryogenic treatment, theworkpiece not only has good wear resistance, corrosion resistance, good surfacequality performance, while able to obtain lower resistivity. Widely used in machinerymanufacturing, an important indicator of copper and its alloys in the field of electricalpower is the electrical resistivity.Through the process of testing the same temperature at different times of deepcold, cryogenic research time on the Cr-Zr-Cu alloy welding electrodes and hard andsoft copper wire affect state law. Using optical light microscopy, X-ray diffractionanalysis (XRD), EDS and other means of cryogenic materials were analyzed beforeand after the sum of cryogenic treatment on the mechanism of copper and its alloys.By comparing the microstructure before and after images of cryogenicprocessing Cr-Zr-Cu alloy welding electrodes, found along the Cu matrix grainboundary precipitation of Cr atoms, with the extension of cryogenic time, Cr atomsformed gradually gathered round particles grow phase. By comparing themicrostructure of copper wire image, twin phenomenon found in their tissues, and theformation of twinning organization.Cryogenic treatment obtained by XRD results Cr-Zr-Cu alloy so that theintensity of the spot welding electrode main diffraction peaks of the diffraction planeis reduced from2%to15%range, and changing the preferred orientation of somegrains in the alloy Reply cryogenic formed during recrystallization texture.By measuring the resistivity of different cryogenic time Cr-Zr-Cu alloy weldingelectrodes and found that with the extension of cryogenic time, the resistivity of themore obvious decline electrode and insulation6h maximum drop of3.89%. But whenthe time reaches21h, changes stabilized. The fundamental reason is cryogenic alloysorganizational structure changes, changing the crystal lattice structure of the material,weakening the scattering of electrons in the material, electrons more easily byreducing the resistivity.Meanwhile, after the cryogenic treatment welding test was found that Cr-Zr-Cuspot welding points in the lifetime of the electrode is increased more than200points,effectively reducing the amount of spot welding electrodes; consistency after the tensile test was found the mechanical properties of copper wire states increasedslightly, while reducing the resistivity while ensuring a certain mechanical strength,making copper wire can be more extensive and long-term applications.Heat and cryogenic treatment technology made the material of variousperformances had improved further, solved only in the limitations of heat treatmentand cryogenic treatment.