Stainless steel for automotive
A first-of-its-kind investigtion by Outokumpu, leader in stainless steel, and researchers at FKA Aachen, has shown stainless steel to have the world's lowest carbon footprint compared with standard carbon steel and aluminum when considering both the production and use phases.
The body-in-white (BIW) is the stage during vehicle manufacturing where all the individual components of the vehicle body are joined together. Stainless steel provides excellent strength and stiffness to the BIW and its high impact resistance greatly increases the safety of the driver and passengers. Other structural components include items such as cross members, crash boxes, door-side impact beams, pillars and further reinforcing elements. The high ductility, formability and weldability of stainless steel allow for endless possibilities.
Stainless steel is being increasingly used in internal combustion engines due to its strength, toughness, corrosion resistance and excellent high temperature properties. Applications include exhaust valves, head gaskets and pump bodies.
Stainless steel can also greatly improve the fuel efficiency, increase torque and horsepower, and reduce emissions of Gasoline Direct Injection (GDI) components such as high-pressure fuel pumps, fuel rail fittings, connectors and spray nozzles.
Electric traction motors, used in both hybrid and fully-electric vehicles, benefit greatly from fully austenitic stainless steel. It is completely non-magnetic so is ideally suited for electric motor components such as shafts, support discs and shrouds. It also offers excellent heat resistant to temperatures up to 300°C.
A significant challenge for EV manufacturers is the design of safe, light and cost-effective battery compartments to house the large lithium-ion battery packs that provide traction power. In addition to saving weight and high crash resistance, the key factor is heat resistance in case of fire. Unlike typically used aluminum, austenitic stainless steel grades can survive temperatures up to 1300°C for over 10 minutes with only a small deflection.
The exceptional corrosion resistance of stainless steel means that it is now used widely in vehicle exhaust systems, especially around the catalytic converter area, and in components including manifold, downpipe, catalytic converter, resonator, intermediate pipe, and silencer.
Plastic is generally the material of choice for automotive fuel tanks. But, switching to stainless steel can offer a lighter, safer and more durable alternative that offers high resistance against internal pressure. It is also compatible with complex forming operations and is fully recyclable.
Internal components such as seat structures and steering columns require materials that are stiff, resist fatigue, offer high impact adsorption for crash safety and are also suitable for complex forming processes. Stainless steel offers the ideal combination of these properties and also does not require painting.
Stainless steel offers high durability, elegant design, aesthetically pleasing appearance and ease of forming into complex shapes for interior and exterior decorative trim such as door handles and trim strips. The corrosion resistance, toughness and ease of fabrication of stainless steel is employed in a wide variety of small machined parts and accessories including hose clamps, springs, windshield wipers and safety straps.
