Abstract

The specific features of the crystallization kinetics of the ternary Al-Ni-Fe system due to the order of the introduction of the alloying elements are explained in terms of the cluster structure of the melts of binary metal systems Al-Ni and Al-Fe. It was established that the order of introduction of the alloying elements into the aluminum melt determines the formation of a different cluster structure, which is responsible for the mechanism of formation of crystallization nuclei and the formation of the phase composition of alloys. It is assumed that a substantial supersaturation of the solid solution with nickel atoms is associated with the introduction of Al3Ni-type clusters into the aluminum matrix of the Al-3Ni-3Fe alloy. This concept is confirmed by the presence of two exothermic peaks on the DSC curves in the region before the crystallization of the alloy and explains the abnormally high value of Young’s modulus and the high yield stress of the alloy.

Keywords: Crystallization kinetics; Cluster structure of the melt; Thermographic analysis; Young’s modulus