These Guidelines focus on the forming and joining of Advanced High-Strength Steels, but those aspects are only important in the context of how and why steels are used in automotive body structures or other engineered products.
Normal vehicle use involves repeated loading of components and joints, potentially resulting in fatigue failures occurring at stresses lower than otherwise expected. Conventional High-Strength Steel fatigue behavior correlates with their tensile strength. However, in multiphase AHSS grades, the strain distribution between phases within the steel microstructure affects the fatigue response, leading to a fatigue response which may vary depending on the grade and the microstructural approach.
Although lightweight and low cost are certainly important, crash safety is the most critical aspect of structural designs. Steels, especially AHSS grades, offer automakers new options to cost-effectively improve crash performance and achieve lightweighting targets promoting improved fuel economy and a greener life cycle.
The articles in this section address these topics.