VIEWPOINT | THE ROLE OF STEEL IN FUTURE MOBILITY

A mobility future that features electrically powered and autonomously driven vehicles will bring major changes in the design, engineering and materials used in tomorrow’s cars. Steel has been the central material of choice for carmakers for a century. But will that still be true as the definition of personal mobility changes?

Jody Hall, vice president of the automotive market for the Steel Market Development Institute, explains why steel’s value proposition and continual gains in performance will assure its central role in personal mobility for decades to come.

How does electrification affect demand for automotive steel?

Demand for automotive steel is expected to be virtually the same as the electrified vehicle market grows. Advances in battery technology make it possible for OEMs to continue to achieve their lightweighting goals more cost-effectively with steel instead of aluminum, which is significantly more expensive.

Besides, carmakers can simply apply some of the same advanced high-strength steels employed to lighten piston-powered models to their electrified cars. They are especially interested in structural applications for steel, because the body and chassis constitute about half the mass of today’s vehicles. The powertrain contributes about 25%.

It’s worth noting that the mass of the average vehicle sold in the U.S. today is slightly lower than it was a decade ago, even though the mix has swung from 60% cars to 70% trucks. The strategic use of advanced high-strength steel has been a significant contributor to that result.

We’re beginning to see the same effect with EVs. A decade or more ago, electric cars were inevitably tiny two-seaters. But the all-electric models due in the next few years will come in all sizes, thanks to more powerful batteries and lightweighting.

For a much larger investment, carmakers could use more aluminum or carbon fiber to further lighten their electric models. But we see mass-market EV manufacturers spending that money on better batteries instead.

What will happen to demand for steel when EVs begin to capture more of the market?

SMDI believes steel usage in the future will be determined more by the size of vehicles than their power sources. Overall use of steel will be about the same, although some of the applications will change as electrification spreads.

Switching from an IC engine to battery power will drive the need for a structural battery pack enclosure A steel battery enclosure will ensure that batteries are well protected, so a minor fender-bender doesn’t incapacitate the vehicle. High-strength steel in that application provides inexpensive protection, and it frees up more room for the battery system.

How will self-driving cars that don’t crash effect demand for high-strength steels?

It will be many decades before all vehicles on the road are fully capable of driving themselves. In the meantime, we’ll have a large proportion of cars on the road that are piloted by humans. We don’t believe occupants in autonomous vehicles will be eager to give up crash protection anytime soon.

There also will be unforeseen cases even with fully autonomous vehicles where a crash occurs. Therefore, we would not expect regulators to relax safety requirements for these vehicles either.

Tomorrow’s robotic cars also are likely to feature more living-room-style or alternate seating than today’s facing-forward configuration. For the sake of easy entry and exit, these vehicles also appear likely to be designed without the usual center pillars that separate the front and rear rows of seats. To maintain safety and structural stiffness, these designs will still need strong body-side structures, which advanced steels provide.

What about the effect of robo-taxis and car-sharing on steel usage?

Widespread car sharing would have a negative impact on car sales to individual owners. But shared vehicles also face a far more demanding service cycle, which requires a high degree of strength and durability. Even so, they would probably be replaced much more frequently than those in today’s U.S. fleet, which average about 12 years in service.

Will these issues come up at SMDI’s Great Designs in Steel conference this year?

Absolutely. Our all-day conference, now in its 18th year, will be held on May 15 at Laurel Manor in Livonia, Mich.

As always, Great Designs in Steel offers attendees great networking opportunities along with technical presentations and a hands-on look at some of the industry’s latest production applications of advanced steels and manufacturing techniques.

We’ll have keynotes from General Motors and AK Steel and three body-in-white tracks involving the 2019 model Honda RDX, 2019 Jeep Wrangler and 2020 Ford Escape This year’s conference also will feature several presentations on materials and manufacturing, along with displays by two dozen exhibitors, including our SMDI members.

For further details and registration information about this year’s conference, click HERE or visit www.autosteel.org.