Kinetics of the amorphous to icosahedral phase transformation in AlCuV alloys

摘要: Abstract Single phase icosahedral samples are obtained by annealing melt-spun Al 75 Cu 15 V 10 amorphous alloys. The kinetics of this to transformation were measured isothermally and nonisotheramally differential scanning calorimetry from changes in the electrical resistivity. Transmission electron microscopy energy dispersive X-ray analysis indicate that proceeds polymorphically nucleation growth, ruling out a “micro-quasicrystal” model glass system. A standard Johnson-Mehl-Avrami isothermal, data yields Avrami exponents range 2–2.5, which inconsistent with polymorphic transformation. These anomalous exponent arise an inhomogeneous distribution quenched-in nuclei. Fits made kinetic assuming constant rate growth on these An rates fits gives estimate for interfacial between 0.002 J/m 2 ⩽ α 0.015 , demonstrating short order must be similar both sides interface.