Thermal stress damage effect of matrix modified CFRP subjected to lightning

Abstract

Aiming at the carbon fiber reinforced plastics (CFRP) of poor electrical conductivity which will lead to thermal stress damage due to intense Joule effect under lightning strikes, electro-thermal-structure coupling models of CFRP lightning strikes were established. By analyzing the thermal strain, thermal stress and status of the modified and unmodified CFRP, their thermal expansion characteristics were compared. Compared with the unmodified CFRP, the thermal strain peak value of the modified CFRP is respectively increased by 36.33%, 53.92%, 66.62%, and the thermal stress peak value of them is respectively reduced by 22.63%, 26.53%, and 9.45% in the absence of dielectric breakdown. But in the breakdown state, both specimens appear complete delamination damage, the protective effect of matrix modification becomes invalid. The thermal stress damage is found having little effect on the damage morphology of the specimens after lightning strikes by comparing their CT images.