Study Of Continuous Ultrasonic And Pulse Ultrasonic On The Refined Zone And Mechanismof ZL205a Alloy Melt

ZL205A alloy has become one of the important structural materials in the aerospace field due to its high strength,high toughness and other excellent properties.Ultrasonic field treatment of molten metal is an effective method to improve the solidification structure of the casting and enhance its mechanical properties.In this paper,Using the continuous ultrasonic and pulsed ultrasonic treatment of aluminum alloy melts,the effects of different continuous ultrasonic power and continuous ultrasonic power on the microstructure and microhardness of the ZL205 A alloy were investigated.The area of continuous and pulsed ultrasound refined on ZL205 A alloy melt was analyzed.The results are as follows:1?Under the condition of continuous ultrasonic vibration,with the increase of ultrasonic power,the grain size of ZL205 A alloy gradually decreases.The grain size,with the ultrasonic power 1500 W,at the vertical depth of 0mm is reduced by about 56.7% with respect to the absence of ultrasonic.The microhardness is a change of fluctuation which first appeared a slight decrease,then began to rise with the increase of ultrasonic power.Then the microhardness reached the peak and then began to decline.At the same power conditions,with the distance from ultrasonic vibration tool horn to alloy melt increasing,the grain size of the ZL205 A alloy showed an upward trend.And the microhardness of ZL205 A alloy is a V-shaped curve that decreases first and then increases.2?Under the conditions of pulsed ultrasonic vibration,with the increase of pulsed ultrasonic power,the grain size of ZL205 A alloy sample gradually becomes smaller,and the average grain size is the smallest at vertical depth of 0mm when the pulsed ultrasonic power is 1800 W,which is about 120 ?m.The microhardness shows a wave shape with the increase of ultrasonic power.Under the same power conditions,the grain size of ZL205 A alloy gradually increases with the distance from ultrasonic vibration tool horn to alloy melt increasing,while the microhardness of ZL205 A alloy shows a V-shaped curve.The microhardness of the alloy shows a maximum at vertical depth of 0mm and 200 mm.3?Under continuous ultrasonic and pulsed ultrasonic vibration conditions,the fitting graphic of grain size of ZL205 A alloy and ultrasonic power and vertical depth in the ultrasonic power range 600 W to 1800 W was obtained.The fitting graphic of microhardness and ultrasonic power and vertical depth was obtained.The fitting formulas for grain size and microhardness were obtained.4?For the area that is actually effective grain refinement of continuous ultrasound,when the continuous ultrasonic power is 600 W,grain size is refined inconspicuously at each vertical depth.The effective depth can reach 50 mm when the ultrasonic power is 900 W.The effective depth can reach 150 mm when the ultrasonic power is 1200 W.The degree of refinement has deepened continuing to improve ultrasound power.For the area that is actually effective grain refinement of pulsed ultrasound,the effective depth can reach 50 mm when the pulse ultrasonic power is 900 W.The effective depth can reach 100 mm when the pulse ultrasonic power is 1500 W.Continuing to improve ultrasound power,the improvement of refining effect is inconspicuous.The effect of pulsed ultrasonic refinement is weaker than continuous ultrasonic vibration.In this paper,the effect of ultrasonic on the refinement of aluminum alloy melt and the effective depth is obtained.It can provide theoretical guidance for the refinement of alloy microstructure with ultrasonic melt treatment.The ultrasonic effective area will also be developed for ultrasonic equipment,casting size and force design for reference.