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The Ford Fusion Lightweight Concept vehicle at Magna. This is not simply an exercise in removing mass or in trying to make the car as aluminum-intensive as possible. Rather, the approach was to make the vehicle lighter while, at the same time, making it so that it could be made—manufactured—in volume in a cost-effective manner.
While the closure panels of the Lightweight Concept are primarily aluminum, beneath the skin it is more of a mixed material approach. This is not only because steel has some excellent properties when it comes to strength and stiffness, but because the goal was to develop a mass-market, not niche, vehicle.
Since 1975, BMW has been presenting what it calls its “Art Car.” The first was a BMW 3.0 CSL that was designed by Alexander Calder for French race car driver and art aficionado Hervé Poulain. Poulain and Sam Posey actually campaigned the car that Calder has brightly painted with reds and yellows and blues in the 1975 24 Hours of Le Mans. Since then, there have been cars painted by artists including Warhol, Hockney and Koons.
So I walk into a large room in an office building in Troy, Michigan. It is an exhibit of all manner of technological developments, from aluminum structures made from high-pressure, high-vacuum die casting to a transfer case system, named Ecomax, that is completely dry, using electromagnetic actuation in place of hydraulics, thereby providing a smaller, more energy-efficient (through the elimination of parasitic and churning losses) package.
And there is what appears to be a brightly painted BMW Art Car, with reds and yellows and blues arrayed on a dark background.
But there are a couple of things that negate that. First of all, it is a 2013 Ford Fusion, not a Bavarian car. Secondly, at closer inspection, it appears to be not so much a painting as an annotated MRI with labels like “Advanced High-Strength Steel” over the B-pillar and roof rail; “Composite Coil Springs” and “Aluminum Front Subframe” in the appropriate areas.
What’s also unusual is that this isn’t a Ford facility, but the U.S. headquarters of Magna International (magna.com), an automotive supplier that is international in more than title, as it has some 128,000 employees in operations that stretch from Detroit to Frankfurt to Shanghai. This is a supplier that not only provides automakers with chassis, interior, exterior, seating, powertrain, electronic, vision, closure, roof systems, and modules, it actually produces entire vehicles in its Magna Steyr facility in Graz, Austria. This past May it announced that since start of production in 2003, it produced 1-million vehicles for BMW (including the X3 and MINI Paceman and Countryman models).
So why is the Fusion there? Ford calls it the “Lightweight Concept” vehicle. It is, explains Dr. David A. Wagner, technical leader, Ford Vehicle Design Research & Advanced Engineering, a project that he and his team worked on along with personnel from Cosma International, a subsidiary of Magna. The project, which was co-funded by the U.S. Department of Energy, was to develop a multi-material lightweight vehicle that could be affordably produced in production volumes.
The vehicle at Magna, one in seven (including a body buck) to be built, was on its way to the Ford proving grounds in Romeo, Michigan, for serious durability testing.
Jeff Conklin, the Cosma program manager on the project, explains that the goal was to “take as much weight out of the vehicle as possible and then build prototypes using processes and materials that are available in production today.”
So they disassembled a production Fusion, then figured out where and how they would replace materials and components with lighter-weight versions. They reduced the weight of the vehicle by 23.8%, going from the weight of a regular Fusion to that of a Ford Fiesta. And because they looked at this holistically, they also released that by reducing the mass of the body structure, they could replace the four-cylinder engine that powers the Fusion with a three-cylinder, one-liter EcoBoost engine, which is available in the Fiesta.
A couple things that need to be emphasized about the concept:
1. It is mixed-materials
2. It is based on production technology
As for the first point, Del Matharoo, vice president, Engineering, Cosma, says that overall, the body-in-white is 60/40 aluminum/steel. “All of the cost studies we’ve done show that that is a good ratio,” he says. Matharoo explains, “You have to balance the cost equation. It is easy for an engineer to make everything aluminum. But for a vehicle of this size and the volumes we’re talking about, it doesn’t necessarily make sense. Therefore, it becomes a balance, and you try to keep the cost in check. You could even say, ‘Let’s make everything out of magnesium or titanium,’ but it gets more and more expensive. So you’re looking for a balance of cost, weight, strength, and crash performance. That’s what gets you to the 60/40 split.” The closure panels are closer to 75% aluminum.
So there is an array of materials. “A lot of the steel is hot-stamped,” says Conklin, “because it is good for strength and energy absorption.” Which explains the use of steel for the aforementioned B-pillar and roof rails. Cosma has plenty of experience working with Usibor steel from ArcelorMittal (usa.arcelormittal.com); it produces the laser-welded, hot-stamped front door ring for the 2014 Acura MDX.
And there are some composites and magnesium used, as well. But the primary focus is on the aluminum attached with the steel.
Which brings us to the second point about the basis in actual production technology. “The manufacturing challenge was primarily on the joining technology,” says Jim Tobin, Magna International chief marketing officer, Magna Asia president, and long-time manufacturing expert (i.e., before joining the company in 2002, he spent 22 years in the machine tool industry, so he is more than passingly familiar with cutting, forming and assembling materials). “We have to do it at a rate that is acceptable for production.”
“We use self-piercing rivets to join the steel and aluminum,” says Conklin. “Each joint”—and there are approximately 120 of them—“has an adhesive barrier to deal with galvanic corrosion issues.”
Says Matharoo, “We are taking a technology developed for low-volume applications but using them in high volumes.”
The riveting is performed robotically, so rather than having a line of spot welding robots in an assembly plant, there would be a line of robots applying the adhesive and self-piercing rivets.
On the subject of welding, Conklin says that there is some spot welding performed on the steel components and some MIG welding on the aluminum. “Ninety-percent of the joining is with self-piercing rivets.”
Conklin also notes that the adhesive, in addition to providing separation between the steel and aluminum to prevent corrosion, provides benefits including additional strength and stiffness. Conklin says, “This is ready for high-volume production today.”
That said, Ford’s Wagner emphasizes, “This is a research vehicle. We’re not ready to put this into the next Fusion.”
Yes, the 2015 F-150 is an aluminum-intensive vehicle that includes steel in its structure, and yes, Wagner acknowledges that they learned a great deal from the F-150 for the development of the Fusion-based concept. “Ford’s message is about lightweight vehicles with high-efficiency powertrains. This is one of the ways we’re going to meet future fuel economy standards.”
Not far from where the Lightweight Concept vehicle is sitting there is a display with a crossover vehicle liftgate. It’s an all-thermoplastic, fully recyclable liftgate that Magna is producing for the Nissan Rogue. Compared to a comparable steel assembly, it weighs 20 to 25% less. In addition, it can be installed later in the vehicle build sequence than is the case when conventional steel liftgates are used, which provides better access for line workers during build.
Next to that there is an active grille shutter that Magna supplies to Chrysler for use in the Ram 1500, which has been around for a while . . . but then an active front deflector, which is undergoing developmental testing. Fixed air dams, especially on light-duty trucks and utilities that sometimes go off road, are often damaged by being hit by a boulder or whatnot. So the Magna-developed deflector can deploy at speed (say 30 mph); can be retracted by the driver (say through the selection of 4WD low); and is clutched such that in the event of a collision (say with that boulder), it automatically retracts. Magna personnel say that active grille shutters provide a 7 to 8 aero count improvement and the front air deflector a 10 to 12 count. However, if both are used, the result is greater than the sum of the parts: a 22 to 25 aero count improvement.
Then, coincidentally close, is another component that it is supplying to Chrysler, but this one for the minivans. A load floor. It has been providing them for some 10 years when presented with a challenge to make it lighter and at a reduced cost. So they came up with what is officially described as a structure that is a “lightweight cored composite, sandwiched with a high-stiffness polyurethane and fiber matrix.” Sounds rather sophisticated, doesn’t it? It is stronger than the panel it replaces. And lighter, too, on the order of 30+% less mass. But when a cut sample is examined, cut so that the middle of the sandwich can be seen, that material in the middle appears to be corrugated cardboard. Yes, it is paper. But it is sealed with urethane,
so it never sees moisture, so it continues to do its work reliably.
Then there are the aluminum die castings made with “High-Q-Cast.” This process allows the production of large, thin-wall complex castings with wall thicknesses as thin as 1.8 mm. Applications for body structures include pillars, shock towers and floor rails. Applications for chassis structures include engine cradles and suspension links. Because the casting is done under a hard vacuum and at high pressure (e.g., 4,400-ton presses), there is little porosity in the castings, for improved components. An advantage to this process is that unlike typical approaches, which involve making individual parts that are subsequently welded together, this reduces complexity and cost.
And there is the thermoset carbon fiber, Class A exterior closure panel that is being developed for introduction on a production vehicle within the next couple years. Magna has developed its own resin formulation along with chemical suppliers, with the objective of having comparatively quick cycle times. Its objective is to move composites from the niche to the relative mainstream, to where 50,000 units per year makes economic sense. The reason why is comparatively simple: going from steel to aluminum provides a 30% weight save; going from aluminum to composites provides a 30% weight save.
The technologies continue, one after the other. The EYERIS camera-based system for automatic emergency braking. A 12-V lithium-ion battery for start/stop systems. An electric rear axle drive with an integrated electric motor. Mirrors, clutch housings, seats, and on it goes.
Swamy Kotagiri, Magna chief technology officer, explains their approach: “Invention plus commercialization equals innovation.” So because Magna, like most companies, wants to be innovative, it is doing something about it, which is inventing new products and improving processes, so that there can be com-mercialization of its developments either now (e.g., the Nissan Rogue liftgate; the hot-stamped Acura MDX door ring; the Ram 1500 active shutters), or in the future . . . which brings us back to the Lightweight Concept multi-material Ford Fusion. They’re ready with the process inventions, some of which have been commercialized (e.g., high-pressure, high-vacuum aluminum die casting), so they are poised for the execution of the innovation.