ISSN:
1662-9779
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Physics
Notes:
The effect of processing parameters on the semi-solid microstructure has beeninvestigated in the course of semi-solid slurry preparation of A356 Al alloy by ultrasonic vibrationmethod. The A356 melt in temperature of 630660°C was poured into a special metal cup, andexposed to ultrasonic vibration at 20 kHz or isothermal holding for a certain time after vibration.The results show that the semi-solid slurry with primary α-Al crystals smaller than 90 μm and anaverage shape coefficient F S (SF was defined as SF4 A/L2P) above 0.5 could be prepared byultrasonic vibration for a time less than 144 s. In the isothermal holding period after a short time ofultrasonic vibration, the average particle diameter increased with the increase of holding time, butF S decreased at first, and then increased a little. It was discovered that ultrasonic vibration is a goodmethod to prepare semi-solid slurry with fine and relatively round primary crystals due to cavitationand acoustic streaming effects
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/24/transtech_doi~10.4028%252Fwww.scientific.net%252FSSP.141-143.451.pdf