Abstract
Current needs in the design and optimization of complex ballistic protection structures lead to the development of more and more accurate numerical modelling for high impact velocity. The aim of developing such a tool is to be able to predict the protection performance of structures using few experiments. Considering only numerical approach, most important issue to have a reliable simulation is to focus on material behaviour description in term of constitutive relation and failure model for high strain rates, large field of temperatures and complex stress states. In this context, the study deals with the behaviour of two steels including a high strength steel and a structural steel. For this application, the materials can undergo both quasi-static and dynamic loading. Thus the strain rate range studied is varying from 10−3 to more than 103 s−1. Although the high strength steels do not exhibit high strain rate sensitivity, the temperature increases during dynamic loading is inducing thermal softening. Thus, temperature sensitivity is defined up to 500 K under quasi-static and dynamic conditions. Then, experiments are used to define the parameters of several constitutive relations like the Johnson-Cook model or the Rusinek Klepaczko model.
Highlights
The development of protective systems against ballistic impacts usually requires the use of several materials leading to complex structures
This study focuses on the dynamic mechanical behaviour of two distinct steels
The mechanical behaviours of a structural steel and a high strength steel has been studied, with experiments performed at various strain rates varying from 10-3 s-1 to 103 s-1 and various temperature going from 173 K to 473 K
Summary
The development of protective systems against ballistic impacts usually requires the use of several materials leading to complex structures. During experiment real mechanical material behaviour can be directly observed whereas in numerical model constitutive relations are used to describe it. Reliability of these relations is essential to obtain valid results. These material models usually represent the equivalent plastic stress of a material as a function of equivalent plastic strain, strain rate and temperature. The first ones are phenomenological, as they do not take into account any physical phenomenon and are only based on experimental observation These relations have the main advantage of a low number of parameters. The third part shows a comparative study of the different models with the experimental results
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
