Based on this study, some conclusions can be made:Dual-phase steel has significantly higher tensile strength over yield strength ratio than HSLA.Dual-phase steel has higher initial strain hardening at lower strain level than HSLA. However, the n-value determined from 10 percent strain to uniform elongation is similar.Dual-phase shows significant bake hardening from a typical paint/baking temperature cycle, while HSLA shows no back hardening kick up.Dual-phase steel demonstrated significantly higher as-formed strength after forming than HSLA, as expected.Stamping trials and computer simulations of a typical automotive rail show similar formability performance between dual-phase and HSLA with similar yield strength.Computer simulations using incremental finite element analysis (FEA) can accurately predict the formability performance of high strength steels, such as dual-phase steels and HSLA.Dual-phase steel has higher springback than HSLA, as expected.Good correlation has been found between the springback angle and as-formed yield strength. No correlation exists between the springback angle and the as-received yield strength.
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