On the crystallization kinetics and micro-structural transformations of Fe40Ni38B18Mo4 alloys

Abstract

Activation energy for crystallization (E c ) is a pertinent parameter that decides the application potential of many metallic glasses and is proportional to the crystallization temperature. Higher crystallization temperatures are desirable for soft magnetic applications, while lower values for data storage purposes. In this investigation, from the heating rate dependence of peak crystallization temperature T p , the E c values have been evaluated by three different methods for metglas 2826 MB (Fe 40 Ni 38 B 18 Mo 4 ) accurately. The E c values are correlated with the morphological changes, and the structural evolution associated with annealing temperatures is discussed.

Structural, topographical and magnetic evolution of RF-sputtered Fe-Ni alloy based thin films with thermal annealing

“…The alloy is amorphous in nature and commercially available in the form of ribbons, with typical thickness of 20 μm and length of a few centimeters in length. The amorphous structure can be devitrified into a nanocrystalline state by thermal annealing or ion irradiation [5][6][7]. A nanocrystalline morphology is more favorable for superior soft magnetic properties since the microstructure of nanocrystals in an amorphous matrix can yield superior soft magnetic properties compared to their amorphous counterpart [8].…”

“…Various reports are available in literature regarding the kinetics of crystallization of Fe 40 Ni 38 Mo 4 B 16 [6,7,[9][10][11]. The enthalpy of formation and activation energy can be evaluated by employing various methods such as the Kissinger [12], Moyniham [13], and Marseglia [14] techniques.…”

“…The enthalpy of formation and activation energy can be evaluated by employing various methods such as the Kissinger [12], Moyniham [13], and Marseglia [14] techniques. Fe-Ni-Mo-B follows a two-stage crystallization process [6,7,10]. The first stage is the Fe-Ni phase, which crystallizes by primary crystallization; the second phase is (FeNiMo) 23 [6,7,10].…”

“…Fe-Ni-Mo-B follows a two-stage crystallization process [6,7,10]. The first stage is the Fe-Ni phase, which crystallizes by primary crystallization; the second phase is (FeNiMo) 23 [6,7,10]. The as-prepared ribbons are amorphous and crystallization takes place with heat treatments.…”

“…The as-prepared ribbons are amorphous and crystallization takes place with heat treatments. The Fe-Ni phase usually precipitates above 400°C and (FeNiMo) 23 B 6 above 500°C [6,7].…”