Annealing dependencies of magnetic and mechanical properties in iron based amorphous ribbons

Changes of magnetic permeability, magnetizing energy and brittleness with an isothermal annealing time at different temperatures have been observed in Metglas 2605S2 ribbons. Relaxation kinetics of this amorphous ribbon have also been studied with isothermal resistance measurements. Considering less deterioration of mechanical properties and more improvement of magnetic properties, we obtain the optimal annealing condition for this ribbon as at 400°C for 20 min in nitrogen gas. It is confirmed from the resistance measurement that stress relief has been completed and structural relaxation is not so significant after this optimal annealing.