Abstract
In the present study, microstructural evolutions of AE42 magnesium alloy via strain-induced melt activation process and the effect of different process parameters are studied. Scanning electron microscope, metallographic observations, and quantitative metallographic method were used for microstructural characterization. The results show that the consumption of supersaturated aluminum during partial remelting led to a decrease in Al/RE ratio and consequently blocky shape Al2RE starts to appear in the microstructure. Furthermore, it was seen that lanthanum and praseodymium did not contribute in precipitate formation and only improved the hardness of the matrix. The effect of compression ratio on the microstructure of treated alloys was confirmed through the increase of both liquid fraction and entrapped pool as well as the kinetic of microstructural changes. Moreover, the effect of compression ratio and holding time on shape factor, liquid fraction, and particle size of the globular structure were measured. It was found that the best result could be achieved at 35% deformation and 40 min holding of the samples at 610 °C.
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Nayyeri, M.J., Dehghani, K. Microstructure Evolution in As-Cast and SIMA-Processed AE42 Magnesium Alloy. J. of Materi Eng and Perform 23, 3077–3084 (2014). https://doi.org/10.1007/s11665-014-1080-y
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DOI: https://doi.org/10.1007/s11665-014-1080-y