Introduction To The Properties Of Silicon Steel Sheets

Silicon steel sheet is essentially a very low carbon steel sheet with a silicon mass fraction of 0.5% to 5%. According to the use of silicon steel sheet can be divided into motor silicon steel sheet (silicon quality fraction is usually below 2.5%, the thickness is generally 0.5ram) and transformer silicon steel sheet (silicon quality fraction is usually 2.5% to 4.5%, the thickness is generally O.35mm); according to the production method can be divided into hot-rolled silicon steel sheet and cold-rolled silicon steel sheet, and cold-rolled silicon steel sheet according to the degree of grain orientation can be divided into oriented silicon steel sheet (for (for the manufacture of transformers) and non-oriented silicon steel sheet (for the manufacture of motors); according to the working conditions can be divided into silicon steel sheet used in strong magnetic fields (mostly used in the power industry, which is the most common dosage of the largest) and weak magnetic fields used in silicon steel sheet (mostly used in the telecommunications industry), as well as in the frequency of silicon steel sheet and silicon steel sheet used in high frequency. In order to reduce eddy current losses at high frequencies, silicon steel sheets used at high frequencies are usually O.1 to 0.2 ram thick, while those used in pulse transformers can be as thin as 0.05 mm or less.

The magnetic directionality of the iron single crystal and (110) L001J ~ easy magnetization axis [100] parallel to the rolling direction, and (110) surface parallel to the rolling plane, the silicon steel sheet along the rolling direction of the highest magnetic susceptibility, with (110) [001] of the grain orientation of the organization is called Gaussian weave. This directional silicon steel is called grain oriented silicon steel or oriented silicon steel. Oriented silicon steel is used in transformers and requires a higher degree of orientation. This is because, the higher the degree of orientation, the less magnetostriction (so-called magnetostriction is the phenomenon of elongation or reduction of ferromagnetic material in the magnetisation, which is the main cause of transformer noise), the better the magnetic properties of the silicon steel sheet, and to reduce iron loss. Non-oriented silicon steel is used in the manufacture of electric motors.

(1) Classification of silicon steel sheet
A, silicon steel sheet according to its silicon content can be divided into two kinds of low silicon and high silicon. Low silicon sheet containing silicon 2.8% below, it has a certain mechanical strength, mainly used in the manufacture of motors, commonly known as motor silicon steel sheet; high silicon sheet containing silicon 2.8%-4.8%, it has good magnetic properties, but more brittle, mainly used in the manufacture of transformer cores, commonly known as transformer silicon steel sheet. There is no strict boundary between the two in actual use, and high silicon wafers are commonly used to manufacture large motors. B, according to the production and processing process can be divided into hot-rolled and cold-rolled two, cold-rolled and can be divided into grain non-oriented and grain-oriented two. Cold-rolled sheet thickness uniformity, good surface quality, higher magnetic properties, therefore, with the development of industry, hot-rolled sheet has been replaced by cold-rolled sheet trend (China has explicitly requested to stop using hot-rolled silicon steel sheet, which is the early said "cold instead of hot").
(2) Silicon steel sheet performance indicators
A. Low iron loss. The most important indicator of quality, countries around the world are divided into grades by the value of iron loss, the lower the iron loss, the higher the grade, the higher the quality.
B. High magnetic induction strength. In the same magnetic field can obtain a higher magnetic induction of silicon steel sheet, with it manufacturing the volume and weight of the motor or transformer core is smaller, relatively speaking can save silicon steel sheet, copper wire and insulation materials. C. High stacking factor. The surface of silicon steel sheet is smooth, flat and uniform in thickness, and the stacking factor of the core is increased.
D. Good flushability. For the manufacture of small and micro motor cores, this is even more important.
E. Good adhesion of the surface to the insulating film and good weldability.
F. Magnetic ageing
G. The silicon steel sheet must be delivered after annealing and pickling.