Liquid channel segregation and morphology and their relation with hot cracking susceptibility during columnar growth in binary alloys

The segregation and morphology of liquid channels at the last stage of solidification are closely related to hot cracking formation. We use Phase-Field (PF) simulations to investigate liquid channel characteristics during columnar growth of single-crystal and bi-crystal Al-Cu alloys. It is found that the back-diffusion is weak in Al-Cu alloys. Liquid channels in Al-2.0, 3.0 wt%Cu alloys coalesce into droplets above the eutectic temperature …