Abstract
An experimental investigation on the mechanical properties of CFRP scarf joints with impact damage was carried out to understand the relationship between scarf angle and impact characteristics. This research shows the effect of the scarf angle on various characteristics, tensile strength, impact damage, and tensile after impact (TAI) strength. These characteristics were investigated experimentally about four scarf angles of 2º, 3º, 4.5º, and 6º. For the non-damaged specimen tensile test, it was found that the tensile strength decreases as the scarf angles increase. It was thought that the reason of decreasing of tensile strength was decrease of bonded area of scarf joint due to increase of scarf angle. Tensile fracture mode of non-damaged specimens were changed from net tension failure mode to adhesive failure mode as the scarf angles increase. As a result of the cross-sectional observation after impact test, impact damage area was increased by the increasing of scarf angle. At the higher scarf angle, debonding of adhesive layer was increased, but damage of laminate was decreased. It was thought that the damage decreasing of laminate was affected by the energy absorption due to significant debonding in the adhesive layer. For the damaged specimen tensile test, residual tensile strength decreased as the scarf angles increase. It was thought that the residual tensile strength of the scarf joints was affected by the increase of debonding in the adhesive layer at higher scarf angle.
