Non-oriented electrical steel, also called isotropic electrical steel, is featured by magnetic isotropy: its magnetic properties are similar in all directions, which makes it widely applicable to the manufacturing of electrical motors and electronic transformer cores. In China, consumption of non-oriented electrical steel represents about 90% of total electrical steel consumption, underlining its importance in the electrical industry.
Key Takeaways
Magnetic isotropy suits rotating machinery such as motor cores and transformer laminations.
Silicon additions reduce iron loss, the discovery that launched silicon steel.
Cold-rolled non-oriented grades replaced hot-rolled sheets from the mid-20th century.
China produces about 90% of its electrical steel as non-oriented grades.
1882-1900: The Silicon Discovery
During this period, a British expert, R. A. Hadfield, found through research that iron loss could be significantly reduced if a certain amount of silicon was added into steel. This discovery laid the scientific foundation for all silicon steel development that followed.
1903-1940s: Commercial Production Begins
In 1903, America and Germany started to produce hot-rolled silicon steel sheets, initiating the commercial production process of silicon steel. In the early 1940s, production of cold-rolled non-oriented silicon steel started, marking the shift toward the higher-efficiency material used today.
1954-2000: Development in China
In 1954, a Chinese steelmaker started to produce hot-rolled silicon steel, beginning silicon steel production in China. In the 1980s, all countries except China stopped producing hot-rolled silicon steel, as cold-rolled grades proved superior. In 1979, a Chinese steelmaker introduced technology from a Japanese steelmaker to produce cold-rolled non-oriented silicon steel, and in 2000, another Chinese steelmaker introduced medium and low grade cold-rolled silicon steel production technology from a Japanese industrial group.
2008: High-Grade Breakthrough
In 2008, a Chinese steelmaker independently developed technologies and equipment for producing high-grade and high-efficiency non-oriented silicon steel, becoming the world's first manufacturer to realize a comprehensive improvement of the product within the shortest time, raising the performance bar for motor and generator core materials.
Frequently Asked Questions
What is non-oriented electrical steel? magnetic-isotropic electrical steel used for motor cores and transformer laminations, with similar magnetic properties in all directions.
Who discovered that silicon reduces iron loss? British expert R. A. Hadfield, through research in the 1882-1900 period.
When did cold-rolled non-oriented production begin? In the early 1940s, following commercial hot-rolled production from 1903.
How much of China's electrical steel is non-oriented? about 90% of total electrical steel consumption.
Why is magnetic isotropy important? Rotating machinery such as motors needs uniform magnetic properties in all directions for efficiency.
What are non-oriented grades used for? Electrical motors, electronic transformer cores and generator laminations.
