Isothermal heat treatments of an Al–4.8mass%Cu alloy under high magnetic fields

Isothermal heat treatment experiments of an Al–4.8mass%Cu alloy were carried out under different magnetic field intensities, at different temperatures and for different holding times. The influence of high magnetic fields on area fraction of θ phase in the solidified microstructure was investigated. It was found that the area fraction of the θ phase was lower when imposing the magnetic field compared to samples heat-treated without magnetic field. In other words, the magnetic field accelerated the phase transformation to the equilibrium state. In addition, the area fraction of the θ phase was independent of magnetic field intensity. This effect of high magnetic fields on the decreasing of the θ phase was discussed from the viewpoint of the effect of high magnetic fields on diffusion.

► Effects of high magnetic fields on Al-Cu alloy were examined during heat treatment.
► Area fractions of θ phase were measured by a quantitative metallographic method.
► High magnetic fields accelerated the phase transformation to the equilibrium state.
► Experimental result was discussed from the diffusion affected by high magnetic field.