Ford Uses Advanced Steels To Make Vehicles Safer, Lighter, Stronger
– The Ford Five Hundred and Mercury Montego – each awarded the 2005 “Top Safety Pick: Gold” by the Insurance Institute for Highway Safety – have advanced safety features, including dual-frontal and side-curtain airbags. In addition, Ford Motor Company researchers and product designers are applying advanced high-strength steel (AHSS) to make vehicles safer, stronger, lighter, and more fuel-efficient. The Five Hundred and Montego are among the first North American designed cars to use significant amounts of AHSS in A pillars, B pillars, and other safety-related areas. Until the early 1980s, vehicles were made primarily with what's called mild steel. In the early 1990s, high-strength steels – which are up to 40 percent stronger than mild steels – revolutionized the industry. Automakers began using large quantities of these steels in vehicles. Now AHSS – developed over the past five years and is up to triple the strength of conventional high-strength steel – is making its way into the auto industry.Volvo uses HSS/AHSS extensively in many models, ranging from 15 percent in the S40 to 57 percent in its XC90. Likewise, the Mazda6 and Mazda RX-8 use advanced high-strength steels in several body structural parts. The primary area where Ford is using AHSS is in vehicle structural components – 55 percent of the weight of a car is steel – to make them lighter and stronger. Because AHSS is so strong, the gage or thickness of steel used in frames, suspension, and body structures can be made thinner, and thus lighter. All steels have the same stiffness, but not the same strength. Stiffness is steel's ability to resist deformation. AHSS has a higher yield strength – the point at which it permanently deforms – and it has a higher ultimate strength. Because about 40 percent of the parts of a car are stiffness-driven, mild steel is fine; there is no real advantage for these parts to be AHSS. With a strength-driven architecture, the car can be made lighter, which is more fuel-efficient, as well as being stronger and more durable. Besides being used in structural components, advanced high-strength steel can be used in the exterior panels. The 2004 Ford Mustang used AHSS in its door panels, for example. Ford researchers are also looking at utilizing AHSS to make pickup truck boxes stronger and better able to withstand heavy loads. Safety is another key area in which the Research & Advanced Engineering group is working with advanced high-strength steels. For example, a Big Bang team is looking at using AHSS in Super Duty pickup trucks to meet roof-crush regulations. If they can develop a structure that can withstand the g forces on a Super Duty during roll-over, they will cascade that knowledge down into other vehicle programs.