Influence of a static magnetic field on the distribution of solute Cu and interdendritic constitutional undercooling in directionally solidified Al-4.5wt.%Cu alloy

•The Rank Sort method is applied to investigate the enhancement of the solute Cu.•The liquid/solid interface is observed by the means of 3D-CT technology.•Numerical simulation confirms that the dendrite refinement should be attributed to the solute enrichment.