Experimental Study on Rheoforming of Quality Magnesium Alloys

Abstract:

Adopting the rheoforming technology, namely rheo-diecasting (RDC) and rheo-twin-roll casting (RTRC) processes were investigated for preparing of AZ91D and AZ31 magnesium alloy products, and their structure characterization and property evaluation were presented. The trials instruct that both semi-solid and melt-intensive-homogenized rheoforming processes, in which a metal-slurry is treated near liquidus by subjecting a forced homogenization are applicable in fabrication of quality magnesium alloys. The experimental results show that the rheoformed alloys obtain more finely and homogeneously dispersed structures, and superior mechanical properties. The average grain size of the α-Mg was 20-40 μm, and the tensile strength was 250 MPa for RDC AZ91D magnesium alloy sample; The RTRC strips consist of equiaxed grains with a mean size of 50–80 μm, correspond to the tensile strength of 213 MPa and 215 MPa plus the elongation of 5.5% and 8.0% for AZ91D and AZ31 alloy strips respectively. Finally, the AZ31 magnesium alloy sheets with thickness of 1.6 mm were prepared by hot and cold rolling from the initial thickness of 6.5mm RTRC strips.

• Periodical: Solid State Phenomena (Volumes 192-193)
• Pages: 476-481
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.192-193.476
• Online since: October 2012
• Authors: Guo Jun Liu, Jun Xu, Liu Qing Yang
• Keywords: Magnesium Alloy, Melt Intensive Homogenization, rheoforming, Semi-Solid

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