The Electrical and Magnetic properties of some low manganese low aluminium steels

Abstract

In this paper are given the results of a detailed study of the electrical and magnetic properties of several low aluminium, low manganese steels containing aluminium and manganese up to about 4% each. A critical comparison of these steels with the convectional silicon steels used in electrical machinery is also made. These steels have been prepared in the high frequency as well as a direct arc furnace and various de-oxidation procedures. The magnetic properties and the hysteresis loss were determined by drawing the complete magnetisation, and hysteresis curves using the ballistic methods. The electrical properties were determined using the Kelvin Double Bridge. The properties of flow of the better alloys as influenced by various annealing and other heat treatments were also studied. The rolling characteristic of the best alloys have also been carefully examined. It is found that steel with approximately 3% aluminium and 2% manganese has electrical and magnetic properties comparable to the convectional silicon steels. The coercive force for this steel, after suitable heat treatment is about 0.6 oersteds with a hysteresis loss of about 1500 ergs/ cc/cycle for a maximum induction of about 10,000 gausses. The electrical resistivity is approximately 55-60 micro-ohms/cm. In addition the steel was easily forgeable and rollable.