抄録
Since the discovery of new high permeability alloys “Nimalloy”, the present authors have investigated the effects of additions of other elements on its properties. From a series of experiments, the highest initial permeability of 76000 and the highest maximum permeability of 441000 have been obtained. In Ni–Mn alloys containing Mo, the cooling rate by which the highest permeability is obtained decreases gradually with increasing Mo content. Therefore, in nearly all cases the alloys have been baked at temperatures below the order-disorder transformation point for a prolonged time after slow cooling from 900°C. With increasing Mo addition, both the initial permeability and the maximum permeability of Ni–Mn alloys increase gradually before reaching their peaks and then decrease monotonically. The composition of 77.67% Ni, 18.63% Mn and 3.70% Mo shows the highest initial permeability of 13720 when baked at 400°C for 340 hr after cooling from 900°C at 5°C/hr and the highest maximum permeability of 113400 when reheated at 400°C for 210 hr after cooling at the same slow rate. The coercive force and the magnetic hysteresis loss of the alloy are as small as 0.0240 Oe and 36.24 erg/cm3/cycle, respectively, for a maximum magnetic induction of 5000 G . The intrinsic magnetic induction and electrical resistivity are 8010 G (H=900 Oe) and 58.8 μ Ω-cm (20°C), respectively.
