Grain Refiner Development for Al Containing Mg Alloys

Abstract:

We have found a chemical compound which can refine the grain structure of both commercially used Al-free and Al-containing magnesium alloys. In this work, the addition of novel grain refiner (NGR) on microstructural evolution of two magnesium alloys (AZ91D and AM50) solidified under various cooling rates is presented. A wedge-shaped copper mould was used to achieve continuous variation in cooling rate for both alloys. The influence of addition of the grain refiner for AM50 alloy is investigated for high pressure die casting (HPDC) process. A series of tensile samples were produced to inspect microstructural and mechanical properties. The observed improvement in elongation for grain refiner added samples is correlated with the grain refinement in early solidified crystals that are commonly observed in HPDC products.

• Periodical: Materials Science Forum (Volume 765)
• Pages: 145-149
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.765.145
• Online since: July 2013
• Authors: Leandro Bolzoni, Magdalena Nowak, Feng Yan, N. Hari Babu
• Keywords: Grain Refinement, High Pressure Die Casting (HPDC), Mg Alloy, Solidification Process

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