Numerical and experimental study for AM50 magnesium alloy under dynamic loads

Abstract

Magnesium alloys are widely used in automotive (steering wheel frames) and aerospace due to their lightweight, ductility, energy absorption and castability properties. Finite Element Analysis and design optimisation have driven the improvement of structural crashworthiness, stiffness, strength, durability, and NVH (noise vibration, harshness) performance, making it possible to meet both the safety requirements and weight reduction targets. The accuracy of the numerical methods is strongly dependent on the accuracy of the material models and parameters employed. This paper presents the numerical Simulation of the Charpy test for AM50 magnesium alloy. This standardised high-speed impact test method measures the energy absorbed by a standard specimen while breaking under an impact load. Numerical simulations were performed using Ansys LS-Dyna explicit solver combined with a Johnson-Cook material's law. Then a sensitivity study was performed using Ansys optiSLang to identify which of the input variables (JC parameters, test specimen's dimensions) has the most influence on the output variables (contact force and absorbed energy).