| Silver-based solder is a silver or silver-based solid solution solder,this type of solder has an excellent process performance,e.g.lower melting temerature,good wetting and filling capacity,high strength solder joints.Therefore,it is widely used in the welding of ferrous metals and non-ferrous metals.In the brazing of the High-precision material.Ag45CuZn solder is the most widely grades of silver solder and has a Widely used in carbon steel,Low-alloy steel,stainless steel,Tool steel,Copper and copper alloy.However,because solder Ag45CuZn(Grade:HL303) has a high price,Precious metal silver is often affected by the market,the prices are not stable,it cause confusion and risk to the Enterprises.Therefore,the material scholars has been committed to find a way to reduce the cost and performance with the same silver solder.Electrical pulse processing technology is a new technology to improve the metal solidification.In the solidification process of metallic materials,the role of the the refinement of metallic materials has been confirmed by large number of studies.However,its mechanism of lagging is far behind the experimental research, Therefore,the study of electrical pulse technology on solidification microstructure and the mechanism of material refinement is of importance.The present study is based on the AgCuZn alloy phase map,Ag45CuZn alloy performance as a target,define the components in the U9-E1 lines.study a new type to substitute the Ag45CuZn.At the same time,the self-designed high-energy-density pulse current device(XJDMC-3 type Pulse generator) is used,Appropriate pulse current to the new alloy is imposed to reveal the pulse voltage,Frequency,pulse width to effect alloy solidification structure and properties of the law materials.Tests reveal the detailed mechanism of alloy solidification structure.The experimental shows that the pulse voltage,pulse frequency and the capacitance can influence the silver alloy solidification structure.During the solidification process of Silver alloy,a certain degree of pulse current is imposed to improve the solidification structure,thick dendrite become smaller and have a trend to the massive changes.At the same time,the distribution of the microstructure tends to be uniform.In addition,the size of electric pulse voltage and pulse frequency will be affected the varying degrees alloy solidification structure.Further studies have shown that with the increase of the pulse voltage conducive,microstructure is refined,Pulse frequency has a significant influence in the microstructure as well..However,the higher the pulse frequency is not the best chioce.Tests of the alloy pilot of the sub properties of materials,Strength Limit the solid phase line and liquid line Show that the properties of the silver alloy through electric pulsing,can reach the Performance Indicators.Although the melting point of solid-phase and liquidus line are higher than that of Ag45Cu30Zn25 alloy,it has a high cost performance due to its effective to reduce the silver capacity.On the other hand,as far as theelectric pulsing alloy is concerned,Although microstructure is refined,the segregation is improved,the properties in the intensity of the limits,melting point and sub-humid areas are close to or better than that of Ag45Cu30Zn25 alloy and has a high cost performance,the toughness is still needed to improve as compared with Ag45Cu30Zn25 alloy.Further study is still needed.
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