Two kinds of silver based medium temperature brazing filler metals(45AgCuZnSn and 60AgCuSn) were selected to braze and seal brass flange pipe and copper pipe by high frequency heating brazing. In this paper, the quali...Two kinds of silver based medium temperature brazing filler metals(45AgCuZnSn and 60AgCuSn) were selected to braze and seal brass flange pipe and copper pipe by high frequency heating brazing. In this paper, the quality of the braze was evaluated by immersion ultrasound, and the microstructure of the brazed joint was observed by SEM and EDS. The experimental results show that the high frequency heating brazing can quickly achieve the device sealing;through the ultrasonic flaw detection image calculation, the brazed bonding rate obtained by 60AgCuSn brazing is 87%, and by 45AgCuZnSn brazing is 71%;the cross-sectional area of the brazed joint obtained by two kinds of silver based medium temperature brazing filler metals is observed, the brazed joint obtained by 45AgCuZnSn brazing has defects visual, and a large amount of Zn element gathered in the defects, there is no obvious porosity in the brazed joint by 60AgCuSn brazing,and the bonding layer is dense and coherent. Through the contrast test, the choice of 60AgCuSn alloy brazing can meet the needs of high frequency brazing of brass flange pipe and copper pipe.展开更多
In a procedure for electrolytic dissolving pure copper and common brasses, the approximate electrochemical mole mass(k) of the sample was determined in accordance with the brand of the sample, a stitable electrolyte w...In a procedure for electrolytic dissolving pure copper and common brasses, the approximate electrochemical mole mass(k) of the sample was determined in accordance with the brand of the sample, a stitable electrolyte was selected to make the current efficiency equal to 100%, and then the dissolved mass of samples was calculated according to Faraday's law(m=klt).Three representative samples were sampled by the electrolytic dissolution method and the calculated dissolved amounts were equal to the values by weighing the anode.The cxperimental results of zinc and copper in the anode liquor are in agreement with certified values.展开更多
Copper plates ,brass plates and copper/brass plates were friction stir welded with various parameters. Experimental results show that the microstructure of the weld is characterized by its much finer grains as contras...Copper plates ,brass plates and copper/brass plates were friction stir welded with various parameters. Experimental results show that the microstructure of the weld is characterized by its much finer grains as contrasted with the coarse grains of parent materials and the heat-affected zones are very narrow. The microhardness of the copper weld is a little higher than that of parent plate. The microhardness of brass weld is about 25% higher than that of parent material. The tensile strength of copper joints increases with increasing welding speed in the test range. The range of parameters to obtain good welds for copper is much wider than that for brass. When different materials were welded, the position of copper plate before welding affected the quality of FSW joints. If the copperplate was put on the advancing side of weld, the good quality of weld could be got under proper parameters.展开更多
The possibility of substituting 72.5Cu-22.7Zn-3.4Al brass for phosphorus bronze in some case that is now extensively used for elastic component,and purifying the scrap copper for recycling metal was investigated. By a...The possibility of substituting 72.5Cu-22.7Zn-3.4Al brass for phosphorus bronze in some case that is now extensively used for elastic component,and purifying the scrap copper for recycling metal was investigated. By adding a little amount of rare earth Y into scrap copper and 72.5Cu-22.7Zn-3.4Al brass to research their structure and characteristics,especially the electric conductivity for scrap copper and HV for the brass were researched. The results show that the tensile strength,elongation and electric conductivity(IACS) of 0.38 mm strip of scrap copper with 0.04% Y,are 213.8 MPa,23% and 98.5% that suit for the elastic components. The tensile strength,elongation and HV of 0.25mm strip of the brass with 0.03% Y are 665.1MPa,2.86% and 226 that satisfy the usage requirement for the elastic components. Meanwhile,the cost is cheaper than phosphorous bronze because of implying 22.7% zinc in the brass,which has the actual application value.展开更多
基金supported by the National Key R&D Program of China(Grant No. 2017YFB0305702)。
文摘Two kinds of silver based medium temperature brazing filler metals(45AgCuZnSn and 60AgCuSn) were selected to braze and seal brass flange pipe and copper pipe by high frequency heating brazing. In this paper, the quality of the braze was evaluated by immersion ultrasound, and the microstructure of the brazed joint was observed by SEM and EDS. The experimental results show that the high frequency heating brazing can quickly achieve the device sealing;through the ultrasonic flaw detection image calculation, the brazed bonding rate obtained by 60AgCuSn brazing is 87%, and by 45AgCuZnSn brazing is 71%;the cross-sectional area of the brazed joint obtained by two kinds of silver based medium temperature brazing filler metals is observed, the brazed joint obtained by 45AgCuZnSn brazing has defects visual, and a large amount of Zn element gathered in the defects, there is no obvious porosity in the brazed joint by 60AgCuSn brazing,and the bonding layer is dense and coherent. Through the contrast test, the choice of 60AgCuSn alloy brazing can meet the needs of high frequency brazing of brass flange pipe and copper pipe.
文摘In a procedure for electrolytic dissolving pure copper and common brasses, the approximate electrochemical mole mass(k) of the sample was determined in accordance with the brand of the sample, a stitable electrolyte was selected to make the current efficiency equal to 100%, and then the dissolved mass of samples was calculated according to Faraday's law(m=klt).Three representative samples were sampled by the electrolytic dissolution method and the calculated dissolved amounts were equal to the values by weighing the anode.The cxperimental results of zinc and copper in the anode liquor are in agreement with certified values.
文摘Copper plates ,brass plates and copper/brass plates were friction stir welded with various parameters. Experimental results show that the microstructure of the weld is characterized by its much finer grains as contrasted with the coarse grains of parent materials and the heat-affected zones are very narrow. The microhardness of the copper weld is a little higher than that of parent plate. The microhardness of brass weld is about 25% higher than that of parent material. The tensile strength of copper joints increases with increasing welding speed in the test range. The range of parameters to obtain good welds for copper is much wider than that for brass. When different materials were welded, the position of copper plate before welding affected the quality of FSW joints. If the copperplate was put on the advancing side of weld, the good quality of weld could be got under proper parameters.
基金Project (2006AA03Z522) supported by the Hi-tech Research and Development Program of ChinaProject (50704006) supported by the National Natural Science Foundation of ChinaProject (550033) supported by the Natural Science Foundation of Jiangxi Province, China
文摘The possibility of substituting 72.5Cu-22.7Zn-3.4Al brass for phosphorus bronze in some case that is now extensively used for elastic component,and purifying the scrap copper for recycling metal was investigated. By adding a little amount of rare earth Y into scrap copper and 72.5Cu-22.7Zn-3.4Al brass to research their structure and characteristics,especially the electric conductivity for scrap copper and HV for the brass were researched. The results show that the tensile strength,elongation and electric conductivity(IACS) of 0.38 mm strip of scrap copper with 0.04% Y,are 213.8 MPa,23% and 98.5% that suit for the elastic components. The tensile strength,elongation and HV of 0.25mm strip of the brass with 0.03% Y are 665.1MPa,2.86% and 226 that satisfy the usage requirement for the elastic components. Meanwhile,the cost is cheaper than phosphorous bronze because of implying 22.7% zinc in the brass,which has the actual application value.
