Optimizing the Bendability of Advanced High Strength Steels for Automotive Applications

点击翻译按钮获取中文摘要

This project aims to improve the competitiveness of ArcelorMittal Dofasco within the North American automotive supply chain for advanced high strength steel sheet. It does so by addressing a key materials validation requirement imposed by most automotive OEMs and parts suppliers, namely that the steel offer sufficient bendability as measured by standard tests. As the automotive industry moves towards the use of stronger steels, thereby enabling vehicle weight reduction, it must tolerate the concomitant reduction in ductility. This limits the bendability of the material. Developing materials that meet these stringent requirements requires a robust understanding of the microstructural parameters that control sheet bendability. Moreover, new materials developed will be enhance if a clear link can be drawn between bendability and properties that can be measured in a standard tensile test. This project will address both goals through a detailed experimental study of damage and fracture in both tension and bending, using a sophisticated array of in-situ and ex-situ approaches. The materials of interest are a range of steels, all with a nominal strength of 980 MPa but with very different underlying microstructures. The experimental results will provide a robust understanding of the relationship between the underlying microstructure and bendability. The data will then be used as input into a multi-dimensional macro-micro model from which bendability will be predicted based on a knowledge of the microstructure and tensile test properties.