Impact modeling of spot-welded columns fabricated with advanced high strength steels.

摘要

In order to increase vehicle fuel efficiency while improving safety and performance and maintaining affordability, the global steel industry has initiated the use of advanced high strength steels that ultimately result in the design of stronger, lighter and more energy efficient vehicles. Tubular steel columns are extensively used in the automotive body structure due to their inherent capacity to absorb energy on impact. Hence, the objective of this research work is to study the crashworthiness performance of columns made from advanced high strength steels.;To conduct this study, computational simulations are developed to accurately assess the influence exerted in the crush response of the columns by different types of materials as well as geometrical characteristics of the thin-walled structural sections.;Furthermore, it is well known that spot-welding is the primary method of joining in the ground vehicle industry. Therefore, the strength of the spot weld under impact is extremely important to the safety design and durability of automobiles. Thus, in this project such an essential factor is addressed by developing a reliable and practical finite element model to predict the dynamic failure of spot-welds in the sheet metal structures.;It is shown that numerical results of the developed robust finite element model give fairly good agreement with experimental data in terms of collapse profile, deformed column shape, final crush length, and impact peak force.;Throughout the investigation, the finite element model permits the study of several structural and material variables that can be validated by a moderate set of destructive tests. Moreover, the current finite element crash model and the findings in this work can eventually be used to improve the crashworthiness efficiency of steel column specimens and to help meet society's demands for affordable, fuel efficient, environmentally responsible, and safe vehicles.