Ford’s vehicle material choices rely on consumer needs and industry standards
October 2011—Ford Motor Co. doesn’t switch the types of materials it uses in its vehicles just to make changes. “It’s the right material at the right time to meet the performance targets,” says Dr. Matthew Zaluzec, a corporate technical specialist at Ford. “What we are doing is responding to all the needs of our consumers by building the right products with the right performance attributes while maintaining a very, very careful view of legislation and fuel economy and CO2 standards.”
Based in Dearborn, Mich., Ford manufactures or distributes automobiles across six continents. The company has roughly 166,000 employees and 70 plants worldwide. July sales totaled 180,865, up 9 percent over the same month one year ago. “We are encouraged to see the stronger pace of auto sales, along with the continued customer demand for our fuel-efficient cars, utilities and trucks,” Ken Czubay, Ford vice president of U.S. marketing, sales and service, said in a press release.
Lightweighting and fuel efficiency are among the main drivers for material choices and experimentation in automotive, says Zaluzec. The automotive industry is based on stamping products, and the trend is moving toward more use of ultra-high-strength steels because of the need to lightweight vehicles and increase fuel efficiency, he says.
“The higher the strength steel, the thinner the steel can be,” but higher strength steel also can result in formability issues, says Zaluzec. “We do a lot of formability analysis to meet the production capability to stamp the products.”
The company’s engineers conduct rigorous research and testing before adding a new material into a Ford vehicle. “Before we actually stamp a part, we do a lot of generic material testing, coupon testing to measure the tensile strength, yield strength, ductility and fatigue strength, etc. We verify the tensile, the yield and elongation before we start making product,” says Zaluzec. When working with metals, it’s somewhat evolutionary to move from, for instance, a steel hood to an aluminum hood, he says.
Ford can achieve component-level weight savings of 35 percent to 40 percent when substituting aluminum sheet for steel, but aluminum comes at a higher cost, notes Zaluzec. During development of a vehicle, Ford looks at the target fuel economy and CO2 values it needs to meet. “Then we go backwards and say, ‘Can we do it with all steel?’ If the answer is yes, then we go down that path and we continue to work with advanced steels,” he says. If not, the company begins looking at other lightweight materials. Working backward enables Ford to get the right mix of materials to reach the required targets.
Look to the future
Ford’s Research and Innovation Center in Dearborn experiments with metals and builds prototypes for the near-term, mid-term and long-term. In additional to metals, Ford also is looking at current composites already in production, specifically low-density and medium-density SMC (sheet molding compound) composites as well as carbon fiber. “In each case, what we are doing is we are looking at the filler. Can we make the filler that goes into the composite lighter weight? It’s that kind of strategy” that allows us to look at optimizing the materials system while minimizing the cost penalty in light weighting a vehicle, he says.
Composites are unlikely to replace metal in vehicles in the near future. “The metals industry is well poised to meet [automotive] demands, whether I stamp the steel or stamp the aluminum,” says Zaluzec. “The question is, is the composite industry going to grow fast enough to meet the future demand?” The metals industry is mature and can support automotive growth, while the composites industry still is growing and needs time to meet the volume needs of automotive, he says.
Ultimately, Ford finds the right material for its vehicles that will meet the needs of the consumer, meets crash and safety standards and delivers fuel economy, says Zaluzec. “We will look at steel where it is appropriate, aluminum where it is appropriate, magnesium where it is appropriate and composite materials where it is appropriate.” At the moment, “steel has a pretty good foundation in the automotive industry. We see that continuing. We see aluminum growing,” he says. MM