Structural relaxation and crystallization of Fe78B13Si9 amorphous ribbons studied by dilatometry and differential scanning calorimetry

摘要: The structural relaxation and crystallization of Fe78B13Si9 amorphous ribbons were studied by dilatometry differential scanning calorimetry (DSC). An own-built highly sensitive dilatometer was used allowing samples in the form thin ribbon to be heated at a slow heating rate (1.66°C min−1) an ultra-high-vacuum (10−9 torr). Thermal expansion coefficients determined on cooling. Isothermal annealings also performed situ 250, 350 450 °C, for 2 h. mean linear thermal (α × 106) measured between 60 250 °C respectively < 5 as-quenched samples, 6.8 ±0.5 relaxed (whatever rate), 11.8 ± 0.5 crystallized ones. After first resulted shrinkage which after cooling room temperature. increased with temperature limit previous <−2 10−4 250°C, \t-5 \t-8 °C. No further detected during isothermal ° C. Crystallization (between 514 537 °C) more important (\t-50 10−4). DSC determining specimens annealed under same conditions as dilatometric measurements. influence investigated. Results are interpreted reference models previously proposed literature metallic alloys.