Anisotropic electrotechnical strip
Electrotechnical cold-rolled anisotropic steel strip, grades 3421, 3422, 3423, 3424, 3425 that is produced in accordance with the interstate relevant standard.
The main specified parameter for a strip with a thickness of 0.08; 0.10 mm are the unit remagnetising losses at a frequency of 400 Hz and a magnetic induction of 1.5 T.
For a tape with a thickness of 0.05 mm, the main specified parameter is the unit losses at a frequency of 1000 Hz and a magnetic induction of 1.0 T.
The main characteristics of the products can be seen in table 1.
| Steel type | Thickness | Specific losses, W/kg, no more than P 1.51400 | Specific losses, W/kg, no more than Р 1,0/1000 | Coercive force, Ns, A/m, no more than | Magnetic induction, not less than, at magnetic field strength, A/m, V 2500 |
|---|---|---|---|---|---|
| 3421 | 0.08 mm | 22 W/kg | – | 36 A/m | 1.70 T |
| 3421 | 0,05 mm | – | 24 W/kg | – | 1,70 T |
| 3422 | 0,08 mm | 19 W/kg | – | 32 A/m | 1,75 T |
| 3422 | 0,05 mm | – | 24 W/kg | – | 1,75 T |
| 3423 | 0,08 mm | 17 W/kg | – | 28 A/m | 1,82 T |
| 3423 | 0,05 mm | – | 22 W/kg | – | 1,82 T |
| 3424 | 0,08 mm | 16 W/kg | – | – | 1,82 T |
| 3424 | 0,05 mm | – | 22 W/kg | – | 1,82 T |
| 3425 | 0,08 mm | 15 W/kg | – | – | 1,82 T |
| 3425 | 0,05 mm | – | 20 W/kg | – | 1,82 T |
As can be seen from table 1, the tape can be produced of grades 3421-3425, that match different value of unit losses. For a tape with a thickness of 0.08-0.10 mm, unit losses vary from 15 to 22 W / kg; for a tape with a thickness of 0.05 mm – from 20 to 24 W / kg. Magnetic induction in a field with a strength of 2500 A / m should be at least 1.82 T for higher grades and at least 1.75 T for lower ones.
At a voltage of 2500 A/m, the force characteristic of the magnetic field according to the norms corresponds to the indicator of 1.82 T for the 3425 brand and 1.70 T for the 3421 brand.
The properties of the tape are evaluated during magnetic tests performed by the manufacturer in accordance with the characteristics required by the consumer. We have the appropriate certificate.
Magnetically soft electrotechnical alloys are usually used in products that require the highest resistivity, high permeability, minimal coercive force and residual magnetism (Fig. 1).
Pic.1
The most common method of producing thin strips is the method of roll rolling without intermediate annealing. For this, special rolling mills are used. We perform high-speed rolling on a 20-roll mill with impressive precision tolerances. The best result is achieved thanks to the small work rolls of the machine, which have great rigidity.
If the crystal structure of the atoms of the alloy is aligned, that is, all atoms face the same direction, this metal will be magnetic. Therefore, rolling is carried out with maximum crimping for the first pass – about 60%, which guarantees a slight misorientation of the grains of the primary matrix with respect to their direction, as well as the appearance of grains oriented in the direction of the best magnetization. Thus, the magnetic flux density reaches a high level. Due to good surface quality, small recrystallization grain size and optimal recrystallization texture, our cold-rolled strip exhibits improved magnetic properties at a field strength of 2500 A/m.
The excellent rigidity of the work rolls ensures a difference in thickness of only five microns, along and across the roll. The smallest thickness of the tape eliminates the problematic moments associated with the calculation of the filling factor of the magnetic core.
An important stage is the application of an electrically insulating aluminum-magnesium phosphate layer, 1-2 microns on each side of the tape, according to GOST standards – ≤ 5 microns for each layer. The coating is homogeneous, heat-resistant up to 8500C, the electrical resistance meets the standards (20-50 Ohm. cm2 ⩾8 Ohm. cm2), there is no peeling when the tape is deformed. This coating reduces specific magnetic losses to 2 W/kg.
Graphs in fig. 2 show the influence of the electrical insulating coating on the properties of the ETS tape.
Pic.2
The final annealing of the product is considered one of the important points of production. It is carried out in an active environment that has restorative properties.
Pic. 3 shows the dependence of the properties of the product on the environment in which annealing is created.
Pic. 3
The increased requirements for the properties of the tape and the experience of its operation revealed the need to develop new methods.
Considering that the annealing environment has a great influence on the magnetic properties, we have implemented the technology of steel processing in tower and garden furnaces, in a nitrogen-hydrogen environment, as well as in a vacuum and hydrogen atmosphere.
This treatment prevents oxidation, providing decarburization and excellent electrical insulation of the surface of the ETS product. At the same time, the vacuum guarantees both high plasticity and homogeneity of magnetic properties over the entire surface, while hydrogen actively minimizes the carbon content.
Flatness and flatness are key characteristics of rolled sheet quality in the metallurgical industry. The deviation in the flatness of the ETS tape after furnace processing is only 1-2 mm.
We work with customers to tailor the mechanical properties of our products to their application needs.
About the TD TAM metal base in Dnipro
Metallobaza in Dnipro, supplier of sheet metal PP TD TAM is a dynamically developing company that provides metal products for dozens of industries from various sectors of the economy.
You can buy rolled metal from us in an assortment, namely:
- rolled steel (wear-resistant, burr-bearing, for cold stamping and deep drawing, high-strength low-alloy steels; hot- and cold-rolled steels);
- sheet steel (steel plate);
- steel tape (isotropic, anisotropic, cold-rolled, tape made of corrosion-resistant and heat-resistant alloys).
Price list of rolled metal – upon request.
Also, you can order metalworking in Dnipro from us:
- cutting of metal and metal products with gas, plasma, laser;
- bending of pipes and metal;
- mechanical metalworking (turning, milling, boring works).
For consultation and order, please contact the indicated phones.
We sell rolled metal in the city of Dnipro, where our production facilities are located, we also cooperate with customers from other cities of Ukraine (Kyiv, Vinnytsia, Kropyvnytskyi, Poltava, Kharkiv, Rivne, Kherson, Lutsk, Khmelnytskyi, Zhytomyr, Lviv, Sumy, Cherkasy, Zaporizhzhia, Mykolaiv, Ternopil, Chernihiv, Ivano-Frankivsk, Odesa, Uzhhorod, Chernivtsi, Luhansk and Donetsk regions and other countries.