Abstract:
An austempered structural steel component for an automotive vehicle, and a method for manufacturing the component, is provided. The structural component can be a twist axle, spring link, control arm, pillar, trailer hitch, bumper, body or suspension attachment bracket for a truck frame, or other chassis, body in white, or safety-related component. The structural component is at least partially formed of medium carbon steel having a bainitic microstructure. The medium carbon steel can include 0.2 to 1.0 wt. % carbon, 0.1 to 3.0 wt. % manganese, not greater than 2.0 wt. % silicon, 0.0 to 0.010 wt. % boron, not greater than 0.1 wt. % sulfur, and not greater than 0.2 wt. % phosphorous. The medium carbon steel provides a yield strength of 900 to 1500 MPa. The structural component is also lighter and can potentially be manufactured with reduced costs, compared to structural components formed from other steel materials.