2008 Volume 49 Issue 3 Pages 650-654
The present study focused on improving the hot ductility and magnetic properties of PC Permalloy. An alloy with a chemical composition of 78.5 mass%Ni-4.3 mass%Mo-2.2 mass%Cu-0.47 mass%Mn-Fe exhibits the optimum permeability, with μ0.005 of 411,200 and μm of 437,400. The P-value of the alloy was 3.43. Addition of Boron caused undesirable deterioration of magnetic properties, while the effects of Magnesium and Calcium on magnetic properties were small. Mill trials using a 50-ton electric furnace revealed that PC Permalloy with a composition of 78.6 mass%Ni-4.2 mass%Mo-2.1 mass%Cu-0.57 mass%Mn-14 ppmCa-4 ppmS-Fe exhibits extremely high permeability (i.e., μ0.005, 233,000 to 499,000; μm, 368,000 to 568,000). High-permeability alloy sheets were obtained by controlling the P-value in the range of 3.45 to 3.49. The hot ductility of the alloy was markedly improved, and ingots and slabs were hot rolled without any corner cracks.
