Open this publication in new window or tab >>2023 (English)In: Metals, E-ISSN 2075-4701, Vol. 13, no 11, article id 1834Article in journal (Refereed) Published
Abstract [en]
To promote the use of newhigh-strengthmaterials in the automotive industry, the evaluation of crashworthiness is essential, both in terms of finite element (FE) analysis aswell as validation experiments. Thiswork proposes an approach to address the crash performance through high-speed imaging combined with 3D digital image correlation (3D-DIC). By tracking the deformation of the component continuously, cracks can be identified and coupled to the load and intrusion history of the experiment. The so-called crash index (CI) and its decreasing rate (CIDR) can then be estimated using only one single (or a few) component, instead of a set of components with different levels of intrusion and crushing. Crash boxes were axially and dynamically compressed to evaluate the crashworthiness of TRIP-aided bainite ferrite steel and press-hardenable steel. Acalibrated rate-dependent constitutivemodel, and a phenomenological damage model were used to simulate the crash box testing. The absorbed energy, the plastic deformation, and the CIDR were evaluated and compared to the experimentally counterparts. When applying the proposed method to evaluate the CIDR, a good agreement was found when using CI:s reported by other authors using large sets of crash boxes. The FE analyses showed a fairly good agreement with some underestimation in terms of energy absorptions. The crack formation was overestimated resulting in too high a predicted CIDR. It is concluded that the proposed method to evaluate the crashworthiness is promising. To improve the modelling accuracy, better prediction of the crack formation is needed and the introduction of the intrinsic material property, fracture toughness, is suggested for future investigations and model improvements.
Place, publisher, year, edition, pages
MDPI, 2023
Keywords
crashworthiness, crash index, third-generation AHSS, 3D digital image correlation, high strain rate, damage modelling
National Category
Applied Mechanics
Research subject
Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-101999 (URN)10.3390/met13111834 (DOI)001113335200001 ()2-s2.0-85177648214 (Scopus ID)
Funder
EU, Horizon 2020, FormPlanet, no. 814519
Note
Validerad;2023;Nivå 2;2023-11-01 (joosat);
Part of special issue: Mechanical Behaviors and Damage Mechanisms of Metallic Materials
CC BY 4.0 License
2023-11-012023-11-012025-03-12Bibliographically approved