抄録
When the specimens of iron-aluminium alloys were cooled in a magnetic field from high temperatures, the percent increase of initial permeability is generally not large, but that of maximum permeability is considerably large and it has a maximum at the concentration of 10.20 percent aluminium. The effect of heat treatment in a magnetic field is small for the concentration of more than 11.5 percent aluminium. When the quenched specimen of 10.20 percent aluminium was annealed again at various temperatures in a magnetic field and cooled in the field, the lowest effective temperature of heat treatment in a field becomes about 225∼250°C. This temperature is 100°C lower than the usual lowest effective temperature for the specimen without quenching. Maximum permeability of the specimen which was quenched at first and heat treated at about 250°C in a magnetic field reaches to the highest value of about 30,000.
