Mechanical Characterization of Dicyclopentadiene and Glass-Fibre-Reinforced Polymer Subjected to Low to High Strain Rate

This work provides a detailed description of the procedures employed to characterize the mechanical behaviour of two materials present in a coach's exterior panels, including glass-fibre-reinforced polymer (GFRP) and neat DCPD (dicyclopentadiene)-based polymers. Tensile tests were conducted at quasi-static, intermediate [1 s^-1, 10 s^-1], and high strain rates [150 s^-1, 250 s^-1] to obtain a comprehensive understanding of their behaviour. The results indicate positive and significant dependence on the strain rate. Additionally, GFRP demonstrates superior energy absorption capacity for higher strain rates, unlike DCPD, which exhibits a higher energy absorption capacity for QS tests. In the case of DCPD, raising the strain rate to 10 s^-1 the maximum stress was not affected but decreased the elongation at fracture. At higher strain rates, there was an increase in maximum stress alongside greater elongation. DCPD maintained consistent stiffness across all rates ranging between 2087 MPa and 2389 MPa, and the tests disclosed a failure mode characterized by numerous surface-transverse fissures. Regarding GFRP, a more pronounced variation in stiffness is observed, decreasing from 11,005 MPa to 4532 MPa at 133 s^-1, recovering to 7288 MPa at 252 s^-1. In addition, the maximum stress and failure elongation tends to increase with the strain rate increase. The detailed analysis of these results provides valuable insights into the mechanical behaviour of these materials under different loading conditions.