Experimental studies and analytical description of two-stage crystallization of the Fe85B15 amorphous alloy

Thermal properties of matter within the model of a two-phase system

“…As distinct from point phase transitions, which occur at a certain value of the external parameter, a diffuse phase transition takes place in a certain range of change of temperature, time or other quantity [17,18]. Such transitions are observed in magnetics (the antiferromagnetic-ferromagnetic transition [17]), relaxors-magnetoelectrics [19,20], amorphous alloys [21,22] and other systems. A diffuse phase transition is accompanied with a transformation of a disordered phase (only the short-range order in the location of components is possible) into a phase with a long-range order.…”

“…2, b). For instance, nucleation in the amorphous alloy Fe 85 B 15 occurs in two stages: up to the temperature of 750 K, the α-Fe crystals are growing (phase α), and then Fe 3 B crystals start nucleating (phase β) [21]. Volume fractions of x 1(α) and x 1(β) crystals for each new phase were calculated using formulas (8) and (10), while the total volume fraction of the forming phase was determined using the formula [25]:…”