Meeting abstract
An investigation of quenching effects on structural relaxation of a metallic glass
Z. Samardžija
; “Energoinvest” RO CIRM, Sarajevo
P. Tomić
; “Energoinvest” RO CIRM, Sarajevo
A. Kuršumović
; “Energoinvest” RO CIRM, Sarajevo
Abstract
Fe₄₀Ni₄₀B₂₀ amorphous ribbons are prepared employing different quenching rates by changing peripheral velocity (V) of rotating copper drum used for melt vitrification. Cross-section area was consistent and proportional to 1/V, which showed stable experimental conditions during ribbon formation. Ribbon width, although decreased with increasing V, was slow-changing function of V. Ribbon thickness, as expected, played main part in cross-section decrease. Differential Scanning Calorimetry measurements were used to study crystallization and low-temperature relaxation. Low-temperature annealing showed exothermal enthalpy relaxation being proportional with quenching rate. Activation energies and crystallization temperatures stayed virtually unchanged in the range of used quenching rates, showing absence of quenched-in crystalline seeds (or phase). For higher quenching rates DSC traces showed presence of higher degree of disorder. However, these quenching-in defects were annealed well before crystallization started its course.
Keywords
Hrčak ID:
339602
URI
Publication date:
20.12.1989.
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