An experimental investigation into localised low-velocity impact loading on glass fibre-reinforced polyamide automotive product

In the automotive industry, more and more engineered parts are shifting from metals to engineering plastics. However localised impact loading and long term ageing effects of under-the-hood plastic components is not well understood. In this paper, localised low velocity impact experiments and simulations were conducted on glass fibre-reinforced polyamide sump to investigate typical flying stones impact scenarios. Complete components were manufactured by injection moulding techniques for the experimental samples. The samples were then subjected to a range of low velocity impact using drop weight tower and flying projectiles from an air gun. Damage assessments were then performed following the experiments. In parallel, finite element analysis using LS DYNA was carried out to virtually benchmark and to predict the strength and fracture behaviour of stressed plastic parts. This has permitted to perform numerous impact tests in different situations with varying parameters. The study results show the significant contribution of the design in terms of shock absorption. The specific sump design with a protective ribbing combined with a superior material increases considerably the impact resistance. The paper will provided detailed discussions and results from both the experiments and finite element analysis investigations.