Structural relaxation in Fe(Co)SiAlGaPCB amorphous alloys

• Published in: Journal of alloys and compounds Vol. 584; pp. 607 - 610
• Main Authors: Borrego, J.M., Blázquez, J.S., Lozano-Pérez, S., Kim, J.S., Conde, C.F., Conde, A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 25.01.2014; Elsevier
• Subjects: Alloys; Amorphous alloys; Amorphous materials; Amorphous semiconductors, metals, and alloys; Annealing; Calorimetry; Condensed matter: structure, mechanical and thermal properties; Disordered solids; Enthalpy; Enthalpy relaxation; Exact sciences and technology; Heat transfer; Heat transmission; Metallic glasses; Physics; Relaxation time; Structure of solids and liquids; crystallography; Transmission electron microscopy (TEM); Enthalpy relaxation; Calorimetry; Amorphous materials; Transmission electron microscopy (TEM); Annealing; Curie point; Medium range order; Amorphous alloy; Iron alloys; Structure relaxation; Heat treatments; Glass transition; Viscoplasticity; Atomic structure; Amorphous state structure; Flow stress; Transition element alloys
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2013.09.074

•Structural relaxation of a Fe(Co)SiAlGaPCB amorphous alloys was studied by DSC.•Two relaxation times were use to fit the experimental values of different magnitudes.•HRTEM images suggest some medium range structural order in the amorphous. The structural relaxation of multicomponent Fe(Co)SiAlGaPCB amorphous alloys was investigated calorimetrically for annealed samples over a wide temperature range below the glass transition temperature. Upon heating, the annealed samples exhibit an endothermic reaction (enthalpy relaxation) starting around the annealing temperature and continuing over a temperature range of about 50–140K, that it is followed by a broad exothermic reaction. Changes in the heat flow curves with annealing temperature and time were analyzed. Experimental values of the overall enthalpy change, ΔH, the peak temperature of the difference in heat flow between the annealed and the as-quenched samples, Tp, and Curie temperature, TC, were fitted by exponential functions including two relaxation times. Values of the two relaxation times are the same for different annealing temperatures regardless the considered property. Saturation values of these magnitudes show a linear dependence with the inverse of the annealing temperature. Tiny domains (2–3nm in diameter) in the matrix observed by spherical aberration corrected high-resolution transmission electron microscopy could be attributed to some medium-range order in the atomic structure of these quenched alloys.