Study On The CuW Alloy Preparated By Grading W Powder

In order to meet the application requirements of high-frequency open circuit conditions of CuW alloys in high voltage capacitor switching,this paper proposed a scheme of preparation method of the CuW alloy with grading tungsten powder,that the method is to get a new CuW alloy with excellent comprehensive performance by adjusting the addition ratio of the submicron tungsten powder,micron-grade tungsten powder and the coarse tungsten powder.Six kinds of W-W sintered neck can be formed in the CuW alloy prepared with tungsten powder with three different kinds of particle size.The way of prepareing CuW alloy can change the strength shortcoming of the tungsten skeleton formed by single sintered neck.This way can also significantly reduced the enrichment copper phase.The hardness,conductivity,arc break resistance and wear resistance of the CuW alloy with different gradation and the bonding suface of CuW/CrCu monolithic materials were tested and analyzed.Research indicates:(1)The microstructure of the CuW alloy prepared by this grading tungsten powder is continued and well-proportioned.The hard tungsten phase and the soft copper phase are uniformly dispersed throughout the matrix which exists little copper enrichment.The conductivity and hardness of the CuW alloy prepared by this grading tungsten powder are high.(2)With the increase of ultrafine tungsten powder and the decrease of coarse tungsten powder,the friction coefficient of CuW alloy reduces from 0.69 to 0.56,the proportion of adhesive wear increases and the proportion of abrasive wear is reducedand,the friction and wear resistance of CuW alloy is improved.(3)With the increase of coarse tungsten powder and the decrease of ultrafine tungsten powder,the erosion pits on the CuW alloy surface after arc erosion increased from 2.1?m 2 to 3.2?m2,the depth of erosion pits decreased,and the voltage resistance strength of the CuW alloy was increased from 4.0x107 V/mto 7.1×107 V/m.(4)With the increase of coarse tungsten powder and the decrease of superfine tungsten powder,the interfacial bonding strength of CuW/CrCu monolithic material increased from 410MPa to 495MPa.The fracture forms of the three kinds of tungsten particles have a great influence on the bonding strength.That the coarse tungsten powder undergoes the transgranular fracture,the micron tungsten powder turns out transgranular fracture or intergranular fracture,the submicron tungsten powder has no fracture or occurs the intergranular fracture.