ISSN:
1662-9779
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Physics
Notes:
Recently, BCAST at Brunel University has developed a MCAST (melt conditioning byadvanced shear technology) process for conditioning liquid metal at temperature either above orbellow the alloy liquidus using a high shear twin-screw mechanism. The MCAST process has nowbeen combined with the twin roll casting (TRC) process to form an innovative technology, namely,the melt conditioned twin roll casting (MC-TRC) process for casting Al-alloy and Mg-alloy strips.During the MC-TRC process, liquid alloy with a specified temperature is continuously fed into theMCAST machine. By intensive shearing under the high shear rate and high intensity of turbulence,the liquid is transformed into conditioned melt with uniform temperature and compositionthroughout the whole volume. The conditioned melt is then fed continuously into the twin-rollcaster for strip production. The experimental results show that the AZ91D MC-TRC strips withdifferent thicknesses have fine and uniform microstructure. The strip consists of equiaxed grainswith a mean size of 60-70μm. The strip displays extremely uniform grain size and compositionthroughout the whole cross-section. Investigation also shows that both TRC and MC-TRC processeswith reduced deformation are effective to reduce the formation of defects, particularly the formationof the central line segregations
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/24/transtech_doi~10.4028%252Fwww.scientific.net%252FSSP.141-143.195.pdf
Permalink