Thermal Analysis during Solidification of Mg-4%.wtAl Alloy during Lost Foam Casting Process

Abstract:

The lost foam casting (LFC) process utilizes the expanded polystyrene (EPS) foam pattern for the production of metallic components. The thermal degradation of the foam pattern has a significant effect on microstructure of the component. Dendrite coherency is important for the determination of the formation of the solidification structure and cast ability of alloys. The effects of the dendrite coherency on grain size in Mg-4Al alloy have been studied using the two-thermocouple thermal analysis technique in the solidified sample. The results also indicate that the grain size increases with the temperature interval between liquids (T_N) and dendrite coherency point (T_DCP), The solid fraction at DCP (f_s^DCP) expressed in percent strongly dependents on the dendrite morphology during solidification.

• Periodical: Materials Science Forum (Volume 686)
• Pages: 371-377
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.686.371
• Online since: June 2011
• Authors: D.H. Hou, S.M. Liang, Rongshi Chen, En-Hou Han, C. Dong
• Keywords: Dendrite Coherency, Lost Foam Casting (LFC), Solid Fraction, Solidification Behavior, Thermal Analysis

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