The viscosity of binary Al–Fe melts in the Al-rich area

• Viscosity of the Al–Fe melts up to 6.5 at.% Fe has been studied.
• Anomalies of the viscosity polytherms with content up to 1.5% Fe have been observed.
• Hysteresis of the viscosity polytherms with content of 3 to 6.5% Fe has been found.
• With an increase of the Fe content the viscosity of the melt monotonically increases.

The temperature and concentration dependencies of the kinematic viscosity of liquid binary alloys of Al–Fe (up to 6.5 at.% Fe) have been studied. For the melts with an iron content less than 1.5% the deviation of the viscosity polytherms from the Arrhenius dependence polytherms has been found presumably due to the structural transformation in liquid aluminum. Hysteresis of the temperature dependences of viscosity of the melts with an iron content of 3 to 6.5% obtained during heating and subsequent cooling has been found. Hysteresis of the viscosity polytherms is the result of irreversible destruction of nonequilibrium atomic microgroups, supposedly, Al5Fe2-type clusters, which are formed by the melting of the Al3Fe crystals.