Ni-Fe-V系合金薄板の実効透磁率およびその応力感受性に及ぼす熱処理と合金組成の影響

抄録

The effective permeability μ_e, and its stress-sensitivity in high frequency fields (H=0.4 A/m, f=1-100 kHz) were investigated for Ni-Fe-V alloys containing 80-84%Ni, 3.5-6.5%V, 0.4%Mn and bal.Fe, severely cold rolled to 0.025 mm in thickness, annealed at 873-1473 K in a pure hydrogen atmosphere and then subjected to the low temperature heat treatment of either controlled cooling or baking. The d.c. magnetic properties, saturation magnetostriction, Curie point and electrical resistivity were also measured.
The optimum annealing temperature to get the maximum value of μ_e shifts to lower temperature with increasing frequency. The optimum baking temperature lowers and the time becomes longer with increasing V content. For example, the temperature and the time for the maximum values of μ_e at 100 kHz in the cases of representative alloy specimens with 5.76 and 6.38%V are about 20 ks at 733 K and 140 ks at 713 K, respectively. The alloys in the region of 82.5±0.2%Ni, 6.0±0.5%V, 0.4%Mn and bal.Fe have the values of high electrical resistivity such as 0.80±0.05 μΩ·m and low magnetostriction, therefore these alloys are excellent in both μ_e and its insensitivity to stress. However, the Ni content of the composition for a maximum μ_e at a higher frequency such as 100 kHz becomes slightly lower than the alloy region mentioned above, while that for a minimum stress-sensitivity factor does not change.