Effects of electromagnetic stirring combining with refiner modification on microstructure of Al-Mg-Mn alloy were observed by SEM （scanning electron microscope）

XRD （X-ray diffraction）. The results reveal that the grain size in the alloy is obviously refined by electromagnetic stirring. The refiner has positive effects on the structure in the alloy in process of electromagnetic stirring

where the grain size becomes more and more refine with increasing in refiner addition and desirable grain size in the alloy can be observed with 0.1% refiner addition. Refining mechanism of electromagnetic stirring was approached by continuously temperature-measuring during solidification process of alloy in mould with refractory materials. It is believed that the electromagnetic stirring results in the appearance of forced convection in the melt and therefore promote the formation and fragmentation of nuclei

which are responsible for the refinement of grain size in the alloy.