Physical Science, Measurement and Instrumentation, Management and Education, IEE Proceedings A

The author reviews the development of electrical steels from hot-rolled silicon iron, first produced around 1905, through the discovery of grain-oriented steels in the late 1930s, to the modern domain-refined high-permeability materials and low-loss nonoriented steels. The use of the steel as the magnetic core material of rotating machines and transformers is considered. This is followed by a discussion of the most important factors which affect the properties of modern electrical steels. Amorphous magnetic materials are now competing in some of the markets traditionally monopolised by electrical steels. The 1990 status of amorphous materials compared to conventional electrical steels is reviewed and possible future developments of these and other competing materials are discussed.