Effect of Cooling Rate on Hot Tearing Behavior of Mg-9Al-1Zn-0.8Ce Alloy

Abstract:

The influence of cooling rate (1.5, 0.3 and 0.1 °C/s) on the hot tearing susceptibility (HTS) of Mg-9Al-1Zn-0.8Ce alloy was investigated by taking advantage of numerical simulation and experimental methods. Filling and solidification processes were observed directly using AnyCasting software. The results demonstrated that the reduction of cooling rate increases the residual melt modulus, deteriorate strain and stress concentration at last stage of solidification, and decrease the hot tearing resistance of alloy finally. The maximum value of HTS was obtained at the average cooling rate of 0.1 °C/s owing to the coarse microstructures and bulk Al₁₁Ce₃. The minimum value of HTS appeared at the rate of 1.5 °C/s thanks to the finest microstructures and a large amount of eutectic. With the increase of cooling rate, hot tearing susceptibility of the alloy shows a rapid reduction at beginning, and a slow decline followed. Besides, morphology of fracture surface and distribution of secondary phase were further discussed.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 61-70
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.61
• Online since: June 2017
• Authors: Wen Jun Liu*, Bin Jiang, Xiao Wei Yu, Fu Sheng Pan
• Keywords: Fracture Morphology, Mg-Al-Zn-Ce Alloy, Numerical Simulation, Residual Melt Modulus

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