Rheo-Forming AZ91D Magnesium Alloy Using Enthalpy Equilibrium Electromagnetic-Stirring Process

Abstract:

An enthalpy equilibrium electromagnetic-stirring process was introduced to semisolid metal processing for rheoforming route. AZ91D was die-casted under normally liquid state of Mg alloy, semisolid state of Mg alloy stirred using traditional EM-stirrer and an enthalpy equilibrium EM-Stirrer, respectively. Further step, effect of pouring temperature on microstructures and tensile properties of castings was researched in the introduced process. Experimental results indicated that samples of rheo-diecasted in the introduced process showed globular primary solid particle microstructure and better comprehensive mechanical properties, typical microstructures consisting of globular primary α-Mg grains and pseudoeutectic organization was observed in the castings with low solid fraction, while in higher solid fraction, the microstructure comprised of agglomerating primary solid particles and Mg₁₇Al₁₂ of divorced eutectic. With decreasing pouring temperature, the density of primary solid particles increased greatly, the size of primary solid particle evolved to coarse.

• Periodical: Solid State Phenomena (Volume 256)
• Pages: 263-269
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.256.263
• Online since: September 2016
• Authors: Xiao Li Zhang*, Tong Min Wang, Chao Zhang
• Keywords: AZ91D, Electromagnetic Stirring, Enthalpy Equilibrium, Rheo-Diecasting

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