A method to control delaminations in composites for adjusted energy dissipation characteristics

A Mixed Numerical-Experimental Method to Characterize Metal-Polymer Interfaces for Crash Applications

“…Parameters for mode II do not change the simulation behavior and have to be evaluated by further experimental work. After recalibration of the cohesive element as suggested in [23] using constant parameters G IC and T, the simulation can recreate the force peak and the rough shape of the curve in general. However, the crack propagation-displacement-curve is too even compared to the experiments and the amount of plasticity in the polymer core cannot be calibrated.…”

“…By measuring the specimen deformation during loading, the delamination propagation is calculated for each loading step, see Figure 5. The algorithm for delamination propagation measurement is based on analyzing the maximum strain in thickness direction [23]. Thus, on the one hand, it is possible to determine the fracture work W F as the difference of the integral under the F-u curve (Equation ( 2)) and the current elastic energy W el with high temporal resolution (Equation ( 3)).…”

“…In [22], it was reported that the greater plastic deformation capacity of a ductile material leads to redistribution of load, so the application of the equation based on the modified compliance methods is open. Therefore, advanced measurement technology is required to determine the crack propagation experimentally and compare it with the simulation results [23].…”

Initiation and Tolerance of Macro-Damage of First Ply (FBF) in a Process of Damaging of Hybrid Multi-Ply Structures Due to Reinforcement Archtecture

“…Based on analysis presented in works of [31,32] a modified form of damage function was adopted, based on elastic modulus, primary E s1 and secondary E s2 : (6) Modulus was used to determine damage functions values of the additional specimens. Following descriptive statistics of D parameter were calculated.…”

“…Progressive damaging process is dependant mostly on mechanical properties of structure of plies, reinforcement architecture and shape and geometry of specimens [4,5]. Process of progressive damaging is beneficial due to large amount of absorbed energy, which main mechanism is delamination [6]. In case when the active force is directed perpendicular to direction of fibers orientation, damage occurs as a result of matrix fracture, mostly in the ply, which has been stretched.…”