Abstract: During automobile collisions, material deformation and failure occurs within milliseconds of impact. In this short time, the structural safety components undergo extremely rapid loading and deformation. Accordingly, the effect of strain rate on material properties is of large importance for automobile designers. In accordance with the high demand for new 3rd Generation AHSS, NanoSteel developed new steel sheet grades with advanced combinations of high strength and high ductility enabled by the formation of a novel nanoscale Mixed Microconstituent Structure. Strain rate sensitivity of this new class of AHSS was evaluated by tensile testing at measured strain rates over a wide range from 0.0008 s-1 to 1,200 s-1. In this paper, the resulting properties and strain rate sensitivity will be discussed in correlation with microstructural studies. Non-traditional response of the material will be demonstrated in comparison with strain rate behavior of existing high strength steel grades.
Authors: S.J.H. Kuhlman, T.V. Machrowicz, C.S. Parsons, A.V. Sergueeva, A.E. Frerichs, B.E. Meacham, S. Cheng, and D.J. Branagan
Keywords: Advanced High Strength Steel, Nanosteel, Strain Rate Sensitivity, Tensile Testing