|About this Abstract
||MS&T23: Materials Science & Technology
||Steels for Sustainable Development II
||Coating-free Press Hardening Steels with Low Carbon Footprint
||Jianfeng Wang, Zhou Wang, Mingfeng Shi, Sarah Tedesco
|On-Site Speaker (Planned)
Press hardening steels (PHS) are produced globally of multi-million tons per year for automotive body-in-white applications. The most used grade is the AlSi-coated 22MnB5, which faces a few challenges from sustainability perspective: (1) the boron-bearing chemistry requires tight nitrogen control (<80 ppm), which has limited the usage of steel scrap, and (2) the use of primary aluminum increases the carbon footprint. In this work, a new coating-free PHS is developed to use 50% steel scraps replacing iron ore. The new steel has excellent oxidation resistance at 950 ℃, thus eliminating the need of an AlSi-coating and post hot-forming shot blasting. In addition, it has a significant lightweighting potential over the 22MnB5, with an ultimate tensile strength about 1.7 GPa and total elongation about 8%. Finally, the new steel can accommodate rapid heating thus enabling a greener and more efficient hot stamping process with less energy consumption and floor space.