ArcelorMittal's product range contains a very broad spectrum of steel grades with specific magnetic properties, including:
These magnetic materials are used in domestic appliances, building industry, mechanical engineering, electrical equipment, motors and generators including electric traction powertrains for automotive.
On top of this, ArcelorMittal offers a comprehensive range of services: technical support, R&D and steel service centres specialised in electrical steels.
Finding innovative (i) and environmentally friendly (e) solutions is essential for the CAR of tomorrow. These values form the core of the name iCARe®. Our iCARe® steels help automakers create environmentally friendly mobility solutions for a greener world.
The iCARe® Save product family comes with guaranteed losses at 400Hz and indicative maximum values at 700Hz. These values are representative of the steel’s behaviour at high frequencies.
Save grades enable you to reduce the iron losses from the stators of synchronous machines. They are particularly useful for reducing iron losses in high-speed hybrid and electric traction machines, and generators which extend the range of electric vehicles.
Save grades are most effective at reducing iron losses from machine parts which are subject to high base frequencies and additional harmonics. Save thus helps to improve machine efficiency, which leads to an increase in power density. Power density can be tuned to create a lighter, smaller machine, or a more powerful machine for a given weight. Driving range is extended as Save reduces machine weight and costs and saves battery energy.
The iCARe® Torque product family comes with guaranteed losses at 400Hz and indicative maximum values at 700Hz. These values are representative of the steel’s behaviour at high frequencies.
Torque grades assist flux generation, allowing the motor to develop more mechanical output. If mechanical output is not an issue, permanent magnet or copper winding can be reduced to save on costs.
Torque grades are suitable for machines which need high torque at low speeds. They provide the fast acceleration required by hybrid and electric vehicles.
The iCARe® Speed product family comes with guaranted losses at 400Hz and indicative maximum values at 700Hz. These values are representative of the steel’s behaviour at high frequencies.
The Speed grades provide an excellent compromise between mechanical properties and losses.
Speed has been developed for very high speed rotors. This enables manufacturers to make more compact machines for a given mechanical output.
ArcelorMittal’s non-oriented fully processed electrical steels have guaranteed magnetic properties, in accordance with (or exceeding the levels required by) EN 10106:2015. As well as the maximum loss and minimum polarisation levels cited, full magnetic characterisation curves regarding losses, polarisation, permeability and apparent power at different frequencies are available on request.
A full range of these standard grades is available so that a steel grade can be selected according to the specific requirements of each application, from low alloy grades offering the advantage of excellent magnetic permeability, thermal conductivity and punchability to alloyed grades offering the advantage of very low losses, even at higher frequencies.
A wide range of coatings is available, allowing further enhancement of punchability, reduction of interlaminar losses and improvement of corrosion protection.
Fully processed steels are designed for the manufacture of magnetic circuits for motors, transformers and other electrical equipment. The principal applications are in the electrical engineering, domestic appliance, automotive and building industries. Low loss fully processed steels are also suitable for shielding applications at low frequencies (e.g. housings around electrical systems).
The semi-processed grades still need an additional annealing treatment step after the client’s punching process. ArcelorMittal offers semi-processed standard grades and semi-processed high permeability grades. The overall average of polarisation in all directions of the high permeability steel sheet plane is therefore much higher than for the standard products.
The punchability of the semi-processed grades has been optimised by the application of an optimised final skin-pass reduction, after the cold rolling and annealing process. Skin-passing produces a controlled surface roughness, ensuring good material behaviour in the punching presses. This roughness also prevents the strips from sticking during the client’s final annealing treatment. Regarding magnetic performance, skin-passing also plays an important role by stimulating grain growth during the annealing cycle, which results in further reduction of losses and increased permeability of the steel.
The semi-processed high permeability grades allow core weight reduction and increased efficiency of motors and transformers. The improved efficiency achieved reduces machine operating costs and at the same time makes them more environmentally friendly.
Non-alloyed semi-processed electrical steels are designed for small industrial motors, fans and domestic appliances such as washing machine motors, microwave oven transformers and refrigerator compressors.
Alloyed semi-processed electrical steels are designed for similar higher efficiency versions of these applications, as they have lower losses whilst the permeability remains at a good level.
Semi-processed high permeability grades are designed for motors, generators, transformers, converters and ballasts where higher efficiency is required.
Hot and cold rolled pole sheet grades are classified according to their yield strength (EN 10265:1995). As well as guaranteed mechanical properties, they have guaranteed magnetic properties, but unlike other electrical steel grades, their magnetic characterisation is determined under direct current (DC) conditions.
High yield strength values allow cold rolled grades to withstand strong electromechanical forces. These grades perform well on loss and induction levels at 50 Hz, thanks to a special chemical composition.
High yield strength values allow hot rolled grades to withstand strong centrifugal and electromechanical forces, both in static and dynamic conditions.
The DC magnetic properties of both grades are excellent and significantly superior to the requirements of the standard.
Cold rolled pole sheet grades are designed for large high-speed machines because of their excellent combination of mechanical strength and magnetic performance.
Hot rolled pole sheet grades are designed for large high-speed machines because of their excellent combination of mechanical strength and good magnetic performance. Good magnetic properties are of major importance for the performance of the poles, whereas excellent mechanical properties are needed for the rims.
ArcelorMittal’s grain oriented electrical steels (GO) are used in the cores of transformers which reduce or increase the voltage of an alternating current. Their superior magnetic properties and insulating coating significantly reduce electric power losses from the transformer.
Our grain-oriented electrical steels are supplied in the fully processed state and have guaranteed magnetic properties, in accordance with EN 10107:2014.
Grain-oriented electrical steels are supplied in the fully processed state and have guaranteed magnetic properties, in accordance with EN 10107:2014.
These standard (or conventional) grades are available in a range of thicknesses and loss levels, enabling clients to select the most appropriate grade to meet the specific requirements of each application: from the basic 0.35 mm grade to the low loss 0.23 mm. For larger, continuously operated machines such as distribution transformers, low loss is of the utmost importance for transformer efficiency. For smaller, intermittently running machines such as welding transformers, the basic grades may represent a better compromise between material cost and equipment performance. Kerizol insulation is applied for optimum material performance.
Grain-oriented steels are designed for the manufacture of magnetic circuits for transformers, self-induction coils as well as some motor types and other electrical equipment. The principal applications are in the power distribution, rail traction, electrical engineering, domestic appliance and automotive industries. Low loss grain-oriented steels are also suitable for shielding applications at low frequencies (e.g. electrolysis units).
Improved CGO electrical steels are supplied in the fully processed state and have properties exceeding the requirements of the conventional grades described in EN 10107:2014.
Improved CGO electrical steels provide lower losses and higher polarisation levels than conventional CGO grades. The improved CGO grades have a magnetic polarisation at 800 A/m of minimum 1.85 T, which is higher than the EN 10107:2014 requirement of 1.75 or 1.78 T.
This means it is possible to use these grades at a higher working point than conventional grades, and in different applications, such as transformers and self-induction coils. With a higher working point, the transformer can be made smaller, which enables cost-savings in terms of the quantity of magnetic and conductor materials needed. Obviously, a higher working point can lead to higher losses, making the transformer less efficient, which is why ArcelorMittal offers its improved CGO grades only with low losses, so this effect is taken into account.
Improved CGO grades can be used in any application where conventional CGO grades are used, but can be advantageous where there is a need, for instance, to reduce the no-load losses of a transformer. These improved grades should be regarded as a product category between conventional GO and high-permeability GO. HGO has the advantage of further reducing losses and increasing polarisation, albeit at increased product cost. Improved CGO grades find their market in applications requiring improved performance in a cost-efficient way.
ArcelorMittal Technotron s.r.o. manufactures stacked, toroidal, cut, unicore cores and laminations (with cutting of 45 or 90°) from grain-oriented steel in thickness from 0.15 to 0.35 mm.
More information: www.technotron.cz
For manufacturers and automakers who wish to exploit the full potential of ArcelorMittal’s electrical steels, we can offer advanced technical support in many areas including modelling, prototyping and material handling.
As a steel provider, ArcelorMittal also offers our customers all the help they need to choose the most suitable steels. We can also help to design the electrical machine. This level of assistance is possible thanks to our advanced R&D know-how and the high-tech equipment available in our research centres.
Our modelling services enable design engineers to make precise machine calculations. This allows them to reduce the number of prototypes needed before pre-series begin. A minimal amount of prototyping is still needed to prove the machine’s performance. ArcelorMittal can offer small quantities of sheets for first stage Epstein and tensile testing, and for the next stage of laser cutting. In the industrial validation phase, ArcelorMittal can provide small slit coils for punching and machine assembly development.
The production of prototype or series machines can involve production processes that have the potential to degrade the properties of the fully processed steels we have supplied.
Advanced R&D support is available to help customers quantify the impact of material handling processes on the magnetic performance of the machine’s lamination stack.
All our varnishes are environmentally friendly, hydrosoluble and chromium-free.
Each varnish for non-oriented grades (C3, C5, C6) has its own specific properties, such as insulation level, punchability effect, corrosion protection, temperature resistance and weldability. For grain-oriented grades, the C5-G type varnish provides increased surface insulation resistance.
More information :
Image created by MachMedia for ArcelorMittal - All rights reserved © 2016