Colin Chapman, the founder of Lotus Cars, is said to have expressed his philosophy of car-building as: “Simplify, then add lightness.” While expanding safety regulations and consumer demands for technology and comfort make simplification a task easier said than done, automakers are taking the second part of Chapman’s dictum to heart, by using and developing materials that have not been widely used in the automotive industry until recently. As manufacturers look to looming EPA mileage standards, these materials are likely to work their way into more and more cars sold today.
Ford recently demonstrated a couple of examples of this shift in manufacturing. First, Ford has announced that for 2015, the Ford F-150, consistently among the best-selling vehicles in the United States, will switch to a mostly aluminum body, looking to shave hundreds of pounds off the truck’s weight. This represents a major gamble — it is unclear how consumers will react to a switch from steel to aluminum, and the costs to repair body damage to aluminum are significantly higher than when steel panels are damaged, meaning that insurance costs generally rise as well. But the benefit is clear: adding lightness is a clear way of increasing fuel economy, and there is speculation that with the right engine, the F-150 could be rated at or close to 30 m.p.g. highway, a lofty number for a full-size pickup.
In a more futuristic move, Ford also recently unveiled its Lightweight Concept: a Ford Fusion (midsize sedan) with a full palette of weight-saving materials, driving the weight from 3,400 pounds to 2,600 pounds, or about the same weight as a subcompact Ford Fiesta. Techniques included replacing steel with aluminum and magnesium alloys; using plastic body panels (and even plastic suspension components, which are undergoing durability testing for future applications); replacing the seats, wheels, and oil pan with carbon fiber; and using thinner, lighter materials for the glass in the windows and windshield. Many of these components are currently prohibitively expensive for production models (carbon fiber wheels, for example, are currently available as original equipment only on the roughly two million-dollar Koenigsegg One:1). But as manufacturers develop new means of driving down cost (such as by reusing leftover carbon fiber from the assembly of larger components to make smaller carbon fiber components, as BMW is doing), these technologies are likely to work their way down to the cars that the average consumer can afford.
But just because aluminum, magnesium, plastics, and carbon fiber are making headway does not mean that the days of steel are numbered. Steel producers are continuing to find ways to develop stronger and lighter alloys, which allow manufacturers to pursue weight savings by using less steel in the first place. Industry groups have claimed that proper use of high-strength steel can save just as much weight as the use of aluminum, without the finicky properties of aluminum when it comes to repair and replacement. Manufacturers that have used ultra-high-strength steel report that it has several times the tensile strength of conventional steel, and allows both weight savings and enhanced safety benefits.
Suppliers need to stay abreast of these developments, and may find that they can add value by adding lightness, even in unexpected places (like the aforementioned lightweight oil pan). And as new materials are explored, suppliers may need to more closely examine where those materials are sourced. The balancing act, as always, will be to deliver value, without intolerably increasing costs — while $98 titanium bolts are great for seven-figure exotics, they are unlikely to be in widespread use anytime soon.