Electrical steels: past, present and future developments

Abstract

Electrical steels are the most important magnetic materials produced in Europe where the total sales market is around E400 million per annum. Its main use is as the magnetic core material of rotating machines and transformers. When magnetised in such equipment, it dissipates iron losses (as heat) which use up around 5% of all the energy generated in the UK. Over the past 20 years, the quality of electrical steels has improved vastly, because of improved manufacturing techniques and a better understanding of factors which control the magnetic properties. The paper 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 domainrefined high-permeability materials and low-loss nonoriented steels. 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 paper reviews the existing status of amorphous materials compared to conventional electrical steels and concludes by considering how these and other competing materials might develop in the future.

Anomalous loss hysteresis loop

“…Magnetic loss, or iron loss, is commonly divided in three parcels: hysteretic (or quasi static), classical eddy current (or parasitic) and anomalous loss (the term excess loss is often used too). This analysis method has been applied by the industry for decades 1 . Microestructural characteristics affect the three parcels behavior.…”

Effect of Anisotropic Yield Criterion on the Springback in Plane Strain Pure Bending

“…Information Technology and Nanotechnology (ITNT-2016) 572 (7) in the region . Here (8) where , and are the tensile yield stresses in the -, -and -directions, respectively, and is the shear modulus of elasticity.…”

“…For example, the considerable achievements in material science of the electric steels (e.g. increasing magnetic induction and capacitance, cutting electric power losses) became possible mainly due to developing efficient anisotropy of physical properties [7][8].…”

Effect of Cross-Rolling on Microstructure, Texture and Magnetic Properties of Non-Oriented Electrical Steels

“…Non-oriented electrical steels are widely used in electrical generators and motors where the magnetic field is important in all directions [1][2][3] . To achieve adequate magnetic properties in all directions, both grain size and texture have been controlled through different thermo-mechanical processing of these steels [4][5][6][7] .…”