| The high-strength and high-conductivity Cu-Cr-Zr alloy has excellent comprehensive mechanical properties,high strength,relatively high electrical conductivity and good plasticity.In recent years,with the development of new products,new requirements have been placed on the properties of materials,such as high strength and good electrical conductivity.In order to meet the requirements of new materials,this paper designs five alloys of different alloys by adding fine grains and Cu-Cr-Zr alloying elements(Ni and rare earth elements La).The heat treatment of solution-aging treatment was carried out by X-ray fluorescence spectrometer(XRF),scanning electron microscopy(SEM)and X-ray diffractometry(XRD)to study the microstructure and composition of the alloy,and to measure the electrical conductivity and hardness of the alloy.And mechanical properties such as tensile strength.Subsequently,the CuCrZr alloy was subjected to small-energy multi-plastic deformation reatment at room temperature by means of small weight multi-impact and strong plastic deformation.The microstructure,mechanical properties and physical properties of the CuCrZr alloy were tested under different plastic deformation conditions.And the analysis,the effect of small energy multi-shot strong plastic deformation on the microstructure and properties of CuCrZr alloy.Finally,the arc ablation experiments of copper-chromium-zirconium materials under high-voltage arc breakdown of 8kV and 16kV were simulated.The ablation morphology was observed by scanning electron microscopy.The distribution of the withstand voltage strength of the materials was evaluated by statistical methods.Experimental results show:(1)Adding different contents of Ni and La elementis in Cu-Cr-Zr alloy by vacuum arc meting,followed by solid solution aging treatment,the mechanical properties and electrical conductivity of the alloy were improved,including 2.0wt%Ni and 0.3wt%La.The alloy hardness alloy can reach 186HV after solid solution aging treatment,and the conductivity is 57%IACS.The comprehensive performance is better than other groups.(2)The average hardness of CuCrZrNiLa alloy after plastic deformation increases with the increase of deformation.When the deformation variable reaches 90%,the hardness increases from 186HV to 232HV,which increases by 24.7%.The effect is remarkable,but the conductivity decreases by 57%IACS is reduced to 48%IACS,which is 15.8%lower.This is because various defects caused by plastic deformation have a hindrance to conductive electrons,increasing the scattering effect on electrons and causing a decrease in electrical conductivity.(3)The dislocation density of CuCrZr alloy increased greatly after multi-plastic deformation,increasing from 0.2052×1015m-2 to 2.12×1015m-2,which increased by 933.13%.The increase of dislocation density increased the deformation resistance of the material,hardness and Increased strength.(4)The central ablation result of the CuCrZr alloy during ablation is the most serious because the current density at the center of the arc is the largest when arcing.The erosion area increases with the increase of the load voltage.When the voltage acts on the anode and the cathode,the thermal motion of the gas molecules is enhanced,and the gas molecules are decomposed into atoms.If the energy is large enough,the atoms absorb energy and separate into positive and negative electrons.Arc-discharge ablation of the arc is achieved with both acting simultaneously.(5)As the number of breakdowns increases,the oxide formed on the surface of the CuCrZr-based alloy increases,and the increase in oxide can act to disperse the arc.At the same time,the breakdown strength first increases and then remains substantially unchanged.Because of the electric field,positive ions and electrons move toward the cathode and anode at a higher speed.After the cathode surface is affected by positive ions,its energy is transferred to the electrons on the metal surface.Some energy is consumed in thermal vibrations,causing the metal to melt. |
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