PRIMARY CRYSTALLISATION OF INTERMETALLIC COMPOUNDS IN THE Al-Ni-Fe-Mn-Si SYSTEM IN RELATION TO FOUNDRY ALLOYS BASED ON AN ALUMINIUM-NICKEL EUTECTIC

摘要

We have calculated liquidus projections in the typical sections of the Al-Ni-Fe-Mn-Si system up to: 9% Ni, 3% Fe, 3% Mn, and 3% Si (%wt). We have identified concentrations of elements enabling primary crystallisation of the Al3Ni, Al9FeNi, Al3Fe, Al6(Fe,Mn), and Al15(Fe,Mn)3Si2 intermetallic phases. We have demonstrated close agreement of the experimental data and calculated data. Primary crystals of two phases - Al9FeNi and Al6(Fe,Mn) will most likely form during casting to metal moulds in the area of nickalyn compositions. Primary crystallisation of the Al3Ni and Al15(Fe,Mn)3Si2 phases is possible only at higher Ni and Si concentrations respectively, while formation of the Al3Fe phase requires slow solidification achieved through casting to expendable moulds.