Study of dilute Al-Cu solidification by cooling curve analysis

Abstract

The solidification path of a dilute Al-Cu alloy was studied using controlled solidification conditions and thermal analysis. Under equilibrium considerations, below the limit of maximum solubility, an unique phase is expected, rounded by rich non eutectic composition. However, even for dilute compositions, the precipitation of the second phase is present, fundamentally favored by segregation in the liquid and instabilities in the front of solidification. This effect has technological and academic implications, related with the precipitation of intermetallic compounds from the melt.