Damage mechanisms and analytical model of CFRP laminate under low-velocity normal and oblique impacts

Abstract

AbstractThe present work investigates the energy absorption performance of carbon fibre-reinforced polymer (CFRP) laminates subjected to low-velocity normal and oblique impacts. Experimental tests are conducted on laminates exposed to varying impact energies at both normal and oblique angles. The numerical model is developed to simulate the dynamic response of the CFRP. The research employs a combination of experimental and numerical methods to reveal the underlying damage mechanisms. The changes observed in the oblique impact response are explained through an analysis of the damage mechanisms. Analytical models for each energy absorption mechanism are proposed based on the principles of energy conservation and the theory of large bending deformation of anisotropic materials. The energy absorption performance of the laminates under oblique impacts, considering rebound and penetration conditions, is discussed. It is found that the delamination is the primary energy absorption mechanism of CFRP laminate under rebound conditions, while elastic deformation of fibres is the primary energy absorption mechanism under penetration conditions. Furthermore, the energy absorption performance of the laminate is found to be affected by the peak force and effective thickness of the plate, which change with the oblique angle. This paper makes a significant contribution by utilising experimental, numerical, and theoretical approaches to gain insights into the damage mechanisms of laminates subjected to oblique impacts.Keywords: CFRPlow-velocity impactoblique impactdamage mechanismanalytical model Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThe authors acknowledge the financial support provided by the cooperative scientific research project of ‘Chunhui Program’ of Ministry of Education (HZKY20220292), the National Natural Science Foundation of China (51775228), the Natural Science Foundation of Shandong Province under Grant No. (ZR2020ME129), and the support from the International Joint Laboratory on Digital Laboratory of Lightweight Structure for Green Vehicle at the Harbin Institute of Technology for the research collaboration (ITCA10102001). The first author would like to acknowledge the China Scholarship Council (202006170147) during his visit to the Karlsruhe Institute of Technology (KIT).