Inductive measurements of magnetic properties of ribbon materials

Inductive measurements of thin ribbon materials are usually done with wrapped toroidal cores. To avoid this time consuming procedure, measurements can also be performed on short straight pieces in a solenoidal setup. We show that demagnetizing effects should be unimportant for the latter case in determining coercive field, saturation field, and core loss. These two types of measurement were performed on samples of amorphous ribbon material. It was found that there is reasonable agreement for these magnetic parameters as long as care was taken to ensure that the samples were strain-free. Strain is particularly important when the material has significant magnetostriction. Based on demagnetization estimates we would expect agreement on permeability determinations in all but the most extreme cases; in fact results can be quite different for the two measurements. Similarly, we can get rather different answers for coercive field when it is very small. This may be due to uniaxial anisotropy which is different for the two sample geometries. It is concluded that the rapid turnaround in solenoid measurements is particularly useful when optimization of saturation field or core loss is of primary importance. (C) 2004 American Institute of Physics.