Kinetics of phase formation and mechanical properties of multilayer Al–30 at% Cu and Al–60 at% Cu foils with different modulation periods
摘要
In this work, the influence of chemical composition (Al–30 at% Cu and Al–60 at% Cu) and different modulation periods (the sum thickness of one Al layer and one Cu layer) on the kinetics of phase transformations and mechanical properties of multilayer foils produced by electron-beam deposition was investigated. Using X-ray diffraction, SEM, differential scanning calorimetry (DSC), and resistometry, the temperature ranges (130–350 °C) and enthalpy changes for the reactions (160.7–312.5 J/g) were determined. Isoconversional Friedman analysis revealed the multi-step nature of the process and the dependence of activation energy on the extent of conversion. It was found that decreasing the modulation period accelerates phase formation (primary phases Al2Cu and Al4Cu9), significantly increases microhardness (up to 7 GPa) and Young’s modulus (up to 190 GPa), while reducing ductility.