Consumption of silicon steel in the United States in 1976 was approximately 750,000 tons, split equally between crystalline and non-oriented materials, and 550 million kg of low carbon steel (Luborsky et al. 1978). Silicon steel is commonly known as electrical flat steel, cold rolled electrical steel, or simply electrical steel. From 1959 to 1976, the annual output of silicon steel doubled, reflecting the worldwide rise in electricity consumption. Today the main producers of silicon steel are Japan, the Soviet Union and the United States. As in the case of low carbon steel, the main reason for the large amount of silicon steel is also high magnetic induction, low loss, low price. Compared with the two, silicon steel has lower loss and higher price, so silicon steel may play a more important role in the balance of total energy price in the future. Silicon steels are used almost without exception in large rotary machines and transformers, while mild steels are used mainly in small intermittent load motors. In Japan, low carbon steel is generally replaced by low silicon steel (<0.5%Si).
As a result of many years of strong research and development work, the quality of silicon steel was most greatly improved, from 1900 to 1930, the performance improvement mainly came from steel-making technology, carbon and other impurities control technology and hot rolling technology progress. A new breakthrough was made in 1934 when Goss (1934) developed CoE grain oriented material. The {110} plane of most of the grains of this material was nearly parallel to the steel plate plane, and the <001> direction was close to the horizontal rolling direction. He first proposed the limit of core loss at 15kG, while the limit of core loss at 10kG was generally prescribed. Improvements to date have come mainly from the development of modern manufacturing techniques, including the use of alkaline oxygen converter and electric furnace instead of open hearthfurnace for smelting and refining, and continuous hot rolling and cold rolling instead of hot rolling sheet metal. Both oriented and non-oriented materials are manufactured by cold rolling because cold rolling provides better control over size and improved flatness than hot rolling.
