Durability and failure mechanics of woven carbon composites under repeated impact loading in Arctic conditions

Abstract

The rise in demand and interest in Arctic exploration has brought new challenges with regard to the mechanical behavior of lightweight offshore structures with fiber-reinforced composite materials. These materials experience drastic changes and degradation in their macro-and microstructures when exposed to seawater and cold temperatures during service. Therefore, it is critical to have a detailed comprehension of the mechanical behavior and failure mechanisms of these materials in Arctic conditions. Within the scope of the current study, low-velocity repeated impact behavior of carbon fiber/vinyl ester composites in Arctic temperature ($-50\ ^{\circ }\hbox {C}$) is investigated. Impact responses, such as the contact force, displacement and absorbed energy, at four impact energies of 20, 25, 30 and 35 J under repeated impact loading until perforation are determined at $-50\ ^{\circ }\hbox {C}$ and compared against those at room temperature ($25\ ^{\circ }\hbox {C}$). The number of impacts required for perforation, the rate of reduction in impact force, the degree of damage and the failure mechanisms change significantly with varying impact energies and in situ ambient temperatures, and they are elucidated in detail in this paper.