Hot-Rolled 590 MPa Tensile Strength Dual Phase Steel For Structural Automotive Components

The production feasibility of a Mn-Si-Cr-Mo alloy grade of hot-rolled dual phase steel was demonstrated using standard hot strip mill processing. Coils of gauges between 1.8 and 6.0 mm were produced with standard run-out table cooling practice and coiling temperatures. The material has good in-coil property uniformity, a low yield-strength-to-tensile strength ratio compared to HSLA steels, and excellent formability (JIS total elongations typically in excess of 30%). It also has good hole expandability, weldability and fatigue resistance. Production material performed successfully in wheel disc production trials and seems suitable for manufacturing structural automotive parts.