The Effect Of Composite Ultrasonic Field On Semi-solid Structure And Mechanical Properties Of A356Aluminum Alloy

Semi-solid forming technology as an emerging industrial processing technology in21st century, has given high priority by insiders around the world. Many researchershave proposed the preparation of semi-solid slurry methods at home and abroad, whichpower ultrasonic is advantage of significant effect, ease operation and thecharacteristics of the low-power green light by scholars in hot pursuit.The subject in the research group of early large number power ultrasound onexperimental data and results of the preparation of semi-solid slurry, designed acomposite ultrasonic field preparation of metal semi-solid slurry device. The set ofdevices successfully fabricated out of high quality aluminum alloy A356semi-solidslurry.The composite ultrasonic field of the device by two power ultrasonic generator thatpower of1000W and1500W, which made to meet at a certain angle, the angle canbe adjusted. Different angle, resulting in a superposition of two shares of ultrasoniccomposite ultrasonic field strength of the points. When the angle is too large that theultrasonic incident angle is large, then passed to the angle of refraction is greater,extend the time of the superimposed ultrasonic field formed slurry. Ultrasonicattenuation in the semi-solid slurry was quickly, resulting in the formation ofcomposite superimposed ultrasonic field effect weakened, semi-solid slurry preparedtissue grain is too large; When the angle is too small and increasing the inclinationangle of the treatment zone, then the mobility of the semi-solid slurry was increased,more quickly through the treatment zone and the semi-solid slurry have not adequatelyultrasonic vibration treatment, resulting in organizational grains have poor morphology.By the experimental results, when the composite ultrasound on the angle of45°, theorganizations of semi-solid slurry was the best.This paper also discusses the impact of pouring temperature on the aluminum alloyA356slurry tissue. The experimental indicate that the closer the liquidus temperature,the slurry tissue as possible. When the pouring temperature is610℃, the semi-solidslurry prepared the best results. The conclusion of the best process parameters: thecomposite ultrasound on to the angle of45°, the pouring temperature of610°C. Theslurry of the grain size is23.9μm and the shape factor is0.86. In the subsequent rheological forming die experiments of aluminum alloy A356semi-solid, when theforming temperature is610°C, are better able to make solid-phase particles in liquidinclusions lubrication independent sliding without agglomerate with each other causeof coarse grains, this time the tensile strength of the molded member was244.12Rm/MPa, the elongation was20.21%.