The measurement and calculation of pulse magnetization characteristics of nickel irons from 0.1 to 5 microseconds

The paper is supplementary to a previous paper by the author and describes in greaterdetail some aspects of work on the measurement of pulse magnetization characteristics of core materials. Methods and techniques of measurement in the range of pulse durations 0.1¿5 microsec, are discussed and a description is given of apparatus and some measuring components which were used incarrying out tests on three relevant core materials. The materials are Radiometal, Rhometal and Mumetal in carefully prepared samples wound from rolledstrip having thicknesses of 0.001¿0.010 in. Pulse permeability and loss characteristics for severalpulse durations and values of d.c. polarizing field are shown on curves. The effects of these variables on pulse performance are discussed. A conception of the mechanism of pulse magnetization is described and a method derived for determining analytically the theoretical magnitude of eddy currents and losses for any form of pulse which can be represented by a finite number of linear voltage changes. Results obtained by this methodare compared with practical values.