Computational Material Modelling for Damage Prediction of Advanced High Strength Steel

FEA based simulations are extensively used in automotive industry for improving the product design and reducing the time taken for design and prototyping. FEA based simulations require material data as an input in form of material models. Most commonly used material models for simulation of metallic materials are elastic models and elasto-plastic models, which provide very good correlation till ultimate tensile strength (UTS). For simulation beyond UTS value, elasto-plastic material model has to be used along with material model considering the damage accumulation post UTS. For crash like event in automotive crash, required material models should consider the effect of various stress state conditions (Triaxiality) and strain rate sensitivity of materials along with damage accumulation. In LS Dyna solver, MAT_ADD_EROSION material model (GISSMO) along with MAT_024 is widely used for these applications.

This paper will focus on development of GISSMO material model card for advanced high strength steel. Various stress state conditions will be considered along with strain rate sensitive properties. Paper will also cover the MAT_024 material model card which is used in association with MAT_ADD_EROSION for elasto-plastic region. Simulated data of coupons and component will be validated with experimental results.