Aluminium α grain refinement in A354 by rotating magnetic field (RMF)

In this study, the authors show how to build an experiment that can impose rotating magnetic stirring during the solidification of a cylindrical cast with thermal data acquisition. Several experiments with increasing frequency and magnetic intensity were conducted. The discontinuous solidification curves of the castings were acquired by means of a thermocouple connected to a high resolution data recording system. It was found that the grain refinement is obtained by resorting to increasingly higher frequencies and intensities of the magnetic field. The dispersion of the grain size decreases in line with magnetic intensity and frequency. The thermal analysis revealed that important solidification events are conditioned by the magnetic field. Several proposals for grain refinement justification are advanced.