The main feature of advanced composites is the high specific stiffness. However, the complexity in certification and damage control behavior is a restrictive factor for the aeronautical application that meets the mechanical requirements of application and maintenance. In order to measure the physical behavior of crack propagation in laminated composites, there was an absence of studies that consider intra (translaminar) and interlaminar fractures to assess the energy release rate as a function of damage progression in quasi-static and cyclic tests through different levels of initial damage. This work aims to evaluate intra and interlaminar damage propagation behavior through cyclic loading and constant amplitude of polymer composite reinforced with continuous fiber, processed via resin transfer molding. For this purpose, low velocity impact will be applied to laminates with different energy levels to generate the initial damage, in which the application of 4-point bending loading in fatigue will be performed to generate the progression of intra/interlaminar damage, being measured by ultrasonic acoustic inspection microscopy methods. The expected results include: the effect evaluation of the initial fracture through the variation of impact damage energy; the damage propagation behavior of quasi-static and fatigue test, developing a standard method for measure the damage progression; evaluation of the stiffness decay by crack propagation rate; the influence of fiber direction on the intra and interlaminar damage through the use of different fiber orientation; and the analysis of fracture mechanisms via fractographic analysis. The expectation of this project will be parameters characterization associated to intra/interlaminar damage propagation behavior under cyclic loading at constant amplitude.
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