The thesis is entitled “A Study on Sandwich Structures - Development, Mechanical Characterization and Numerical Modeling "
Opponent: Dan Zenkert, KTH, Stockholm
Supervisor: Pär Jonsén
Assistant Supervisor: Jörgen Kajberg, Simon Larsson
Project: FormPlanet and LightFE
Sandwich material is one of the most important materials of the future for vehicles and constructions. A metal sandwich consists of a core and surface plates and has properties to be light while being strong. The dissertation presents new experimental methods for mechanical characterization of sandwich materials and numerical models for simulating the behaviour of sandwich materials. Tools are developed to load sandwich materials, where digital image correlation is used to measure displacement fields and cracks in the sandwich core. Statistical methods are used to analyse the variation in the mechanical properties of sandwich materials. Experimental data are used as input for constitutive models, which simulate materials subjected to lamination. The numerical models are validated against experiments, proving to be consistent, which indicates that the experimental method provides robust data.
The current work presents methods for further increasing the usability of steel in lightweight and has investigated how steel sandwich materials can be simulated numerically with sufficient accuracy and reasonable calculation time. These results open up opportunities for further development and optimization of lightweight constructions.