ArcelorMittal unveils iCARe portfolio of electrical steel solutions for hybrid and electric vehicle motors
ArcelorMittal, the world’s largest steel and mining company, unveiled its first electrical steel product range designed specifically to meet the requirements of the electric vehicle (EV) sector at the Coil Winding, Insulation and Electrical Manufacturing trade fair in Berlin. Electrical steels are specialty steels tailored to produce certain magnetic properties; strips of electrical steel are stacked (laminations) to form electric motor stators and rotors (or the cores of transformers).
The result of a significant investment in research and development, the iCARe portfolio has been created to help carmakers deliver lower CO2 emissions and improved fuel consumption for hybrid vehicles, while also contributing to longer range of pure electric vehicles and a lower total cost of electrification.
The iCARe steels promise to deliver increased power density from electric motors, helping to reduce the size and weight of low-emission vehicles via enhanced energy-efficiency.
The iCARe portfolio includes three distinct grades of electrical steel developed to meet specific challenges presented by the shift towards electro-mobility; all three grades come with guaranteed losses at 400Hz and indicative maximum values at 700Hz. These values are representative of the steel’s behavior at high frequencies.
The iCARe Save range offers very low electrical loss, maximizing use of current batteries and allowing electric vehicles to drive further on one charge.
Save grades 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 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 products ensure the highest levels of mechanical power output from EV motors, generating improved acceleration and ensuring a more dynamic driving experience. 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 steels provide a compromise between mechanical properties and losses. They deliver very high strength, making them suited for the manufacture of high-speed rotors that allow a further weight reduction of the motor. With these three types of iCARe steel, machine designers now have access to the most suitable electrical steel to maximize the efficiency of their motor design.
ArcelorMittal also offers coatings for the iCARe range, designed to further-customize the application of each of the iCARe steel grades. Electrical steel varnishes for non-oriented grades are designed to enhance the behavior of fully processed electrical steels. Their main purpose is to provide inter-laminar insulation and to improve the punchability of these steels.
Each type has its own specific properties, such as insulation level, punchability effect, corrosion protection, temperature resistance and weldability; hence it is material use that determines the optimum choice of varnish. All varnishes have been selected and developed to be environmentally friendly: they are hydro-soluble, chromium-free and butyl glycol-free.
A suite of iCARe Advanced services offer further technical support for automotive customers, encompassing areas including modeling, prototyping and material handling. With this advanced technical service, ArcelorMittal is a real partner in magnetic and mechanical machine design for electric vehicles.
As part of the iCARe project, ArcelorMittal has also committed €90 million (US$112 million) investment in the creation of a new continuous annealing line at its production facility at St-Chély d’Apcher. Potentially capable of producing up to 120,000 tonnes of iCARe steels per annum, this production line will support the development of further breakthrough innovations for the automotive steel sector, helping to meet growing global demand from EV manufacturers.