Steelmaker Says Car Doors Could be 34% Lighter

ArcelorMittal SA says stronger steels and design tweaks could cut the weight of a conventional car door from 40 lbs to about 26 lbs.

The Luxembourg-based steelmaker says its concept door, which uses current high-performance steels, could lower the weight of a C-segment car door to 29 lbs without jeopardizing structural and safety performance requirements.

Even stronger alloys not yet in production, such as ArcelorMittal's Usibor 2000, could shed another 3 lbs, according to the company.

ArcelorMittal's demonstration door uses a combination of high-strength and ultra-high-strength steels, strategically placed reinforcement and a new laser-welded blank inner panel made of unusually thin steel.

Switching to ultra-strong steel also would allow carmakers to reduce door outer panel thickness to 0.5 mm, according to the company. AcrelorMittal did not reveal the cost of its light steel door system, but it says doors made of available high-strength steel can be made for about 30% less than an all-aluminum construction.