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Infrared thermography is used to visualize temperature variations which are linked to thermoelastic effects developing over the surface of a cantilever beam undergoing deflection under cyclic bending tests. Several specimens are fabricated of thermoplastic composite materials, which involve change of matrix and/or reinforcement. More specifically, the matrix is either a pure polypropylene, or a polypropylene modified with the addition of a certain percentage of compatibilizing agent (grafted); the reinforcement being made of woven glass, or jute, fibers. Cyclic bending tests are carried out with the aid of an electromechanical actuator. One surface of the specimen is continuously viewed by an infrared imaging device during deflection. The suitability of infrared thermography to distinguish the small surface temperature variations, depending on both matrix and reinforcement type, has been previously demonstrated. In this work, the matrix is separately analyzed to add information about its role when coupled with either glass, or jute, and in the presence of a certain percentage of a grafting agent., INTRODUCTION Thermoplastic matrix-based composites (TC) offer many advantages over their thermoset counterparts, and then are gaining increasing interest from both their industrial and research relevance. Their main advantages are: potential [...]

This work is concerned with the use of infrared thermography (IRT) to investigate impact damaging of carbon/ epoxy materials. IRT has already proved suitability to visualize thermal effects induced by impact tests, but till now it has been mainly used with thin laminates with little attention toward the thicker ones. The aim of this work is to compare thermal effects evolving on both thin and relatively thick laminates to better validate the use of IRT and to get information useful for the comprehension of composites impact damaging mechanisms. Impact tests are carried out at different energies with a modified Charpy pendulum while the specimen surface opposite to that struck by the impactor is viewed by the infrared imaging device, which collects a sequence of thermal images. The analysis of the temperature variations during impact supplies information about the peak contact force, the initiation of the impact damage as well extension of delamination and of the overall impact affected zone. In addition, impacted specimens are non-destructively evaluated with lock-in thermography; the obtained phase images are compared with thermal images recorded during impact. An integration of results helps to estimate the impact damage location and its size., INTRODUCTION Composite materials and especially carbon fiber-reinforced polymers (CFRPs) are increasingly used in the construction of aircraft primary structural components [1], However, as most types of composites, they exhibit different [...]