Application of differential thermal analysis to investigation of magnetic field effect on solidification of Al–Cu hypereutectic alloy

Investigation of solidification in the Al–25 at.%Cu hypereutectic alloy in magnetic fields has been carried out by differential thermal analysis (DTA). The DTA results indicated that the nucleation temperatures of primary Al2Cu phases and Al–Al2Cu eutectics were lowered and the rates of crystal growth including primary phases and eutectics were reduced although the melting of the alloy was almost not affected in magnetic fields of 6 T and 12 T in comparison with those without a magnetic field. The suppression of nucleation and growth of primary phases and eutectics might be mainly attributed to reduction of diffusion rates of atoms in a magnetic field on the condition of suppression of convections. Primary Al2Cu phases oriented along a magnetic field compared with disorder ones without a magnetic field, which was caused by the magnetic anisotropy.