Energy Absorption Behaviour of Austenitic and Duplex Stainless Steels in a Crash Box Geometry

Abstract

The improvement of the passive safety plays an important role in the development of new steels for automotive parts. At the same time aspects of weight reduction as well as the industrial feasibility have to be considered. Powered by these objectives, the development and application of new steel concepts for various purposes is promoted. For the present investigation especially weight reduction combined with an improvement of the passive safety are emphasised. As example one representative part of the body structure, the crash box, is considered. At the moment different steel grades (dual phase-, TRIP-and HSLA-steels) as well as fibre reinforced materials are applied. New materials for this special purpose have to exhibit outstanding formability, a high capacity to absorb energy during a possible crash and should be cost effective compared to already existing material concepts. During this project different grades of austenitic stainless steels with varying stability were compared to duplex stainless steels and a TRIP grade with regard to their possible application as crash-box material. The austenitic grades show excellent gradual formability according to their strength level. All of them exhibit an extraordinary strain hardening behaviour. The duplex grades show a lower formability but on a much higher yield level. Besides the determination of classical material data such as uni-and multi-axial flow curves, dynamic tensile tests and forming tests for the determination of forming limit curves were performed. The material data were used in the simulation of a drop tower test which is commonly used to evaluate the performance of different materials in car components. The results were then evaluated with regard to the absorbed energy, the folding behaviour and the resulting forces.

Microstructure, Texture, and Tensile Properties of a Severely Warm‐Rolled and Annealed Duplex Stainless Steel

“…The combination of austenite and ferrite provides the advantage of mechanical properties along with corrosion resistance as compared to the usual single‐phase stainless steels. Therefore, microstructure and properties of duplex steels remain topics of much interest . However, in order to widen the applications of DSS, it is important to understand the evolution of microstructure, texture, and properties during thermo‐mechanical processing of DSS.…”

Interfacial Morphology and Bonding Mechanism of Explosive Weld Joints

“…The composite materials of magnesium alloys and austenitic steels can potentially be applied in many automotive and aerospace components [29,30]. A 304SS/AZ31B Mg alloy clad plate was fabricated by explosive welding.…”

Microjoining developments of ASS316L/AZ31 TLP bonds using Cu and Ni high temperature solid state diffusion

“…On the other hand, the low density of wrought magnesium alloy AZ31 provides an alternative material to replace heavy structural components with lighter modules in automotive and aerospace industries whereweight reduction and fuel consumptioncost saving can be achieved [5][6][7] . Recently, many automotive and aerospace components are manufactured using magnesium alloys [7,8] and austenitic stainless steels [9,10] . However, joining of these dissimilar alloys still presents a challenge because of thesubstantial distinction in their physical and metallurgical properties [11][12][13] .…”