Lightweigth impactor prototype for a drop tower testing machine, made on carbon fiber composite and additive manufacturing

Abstract

[EN] One of the most commonly used techniques to characterise the impact behaviour of viscoelastic materials is the drop weight impact test. The University of Málaga has an Instron CEAST 9350 for testing at speeds of up to 24 m/s. Currently, the lowest available mass is 2,4 kg, which is excessive for low-stiffness materials. The aim of this study is to design, calculate, and manufacture a lighter impactor, made from carbon-epoxy laminates and continuous carbon fibre additive manufacturing. Geometric constraints have been imposed to ensure its integration into the Instron CEAST 9350, as well as a maximum impact force of 22,5 kN. The proposed solution has been validated through explicit dynamic analysis using LSDYNA. As a result, a mass reduction of approximately 50% has been achieved. The developed structural concept will enable further mass reduction in the future for lower impact forces, depending on the material to be tested.