Damage of woven composite under translaminar cracking tests using infrared thermography

Abstract

The aim of this work is to increase the study of the notch translaminar propagation of the woven structures, using the InfraRed Thermography (IRT). A test of notch propagation under quasi-static traction was developed and used to study the failure phenomena on two different draping sequences. For each study, a local estimation of dissipated energies, associated with different damages, is carried out using the measurement of the surface temperature field. The study of heat source fields combined with micrographic observations allowed to define the matrix microcracking as the predominant damage phenomenon in crack tip. The critical energy release rate, obtained using IRT, corresponds to critical energy release rate reported in the literature for translaminar rupture of laminates. Furthermore, when brittle cracking develops in a thermosetting matrix laminate, the majority of irreversible mechanical energy (>90%) is dissipated as heat. In the case of brittle cracking, the developed method proves to be an efficient alternative technique for the local measure of energy release rate, even in cases where the variations in stiffness due to cracking phenomena remain low.

Experimental and numerical analysis of Carbon Fiber Reinforced Polymer notched coupons under tensile loading

“…6) seems to indicate such a failure mode [53]. The others are less energetic: they increase the temperature locally by a few tenths of a degree [53,54]. Once the propagation had begun, emissions of heat were detected on the right side of the notch (close-up for coupons n°1 , 2 and 3, Fig.…”

“…A local increase in temperature of about one degree (Fig. 6) seems to indicate such a failure mode [53]. The others are less energetic: they increase the temperature locally by a few tenths of a degree [53,54].…”

Damage detection versus heat dissipation in E-glass/Epoxy laminated composites under dynamic compression at high strain rate

“…For [±60] 20 , tested specimens, the equivalent thermal image indicates an elevation in the temperature of specimens from 75 to 190°C. According to [35,36] important deformation leads to the large temperature rise during the heating stage around the cracked areas and the maximum heat was observed when crack depth is larger.…”

Compressive intralaminar fracture toughness and residual strength of 2D woven carbon fibre reinforced composites: New developments on using the size effect method

“…While the crack tip is already difficult to locate in stable mode I tensile fracture toughness tests [17], its location becomes even more of a subjective estimate in CC testing, especially when measured optically [22]. Although other less subjective crack measurement techniques have been employed in literature, including Digital Image Correlation (DIC) [22], and infrared thermography [23], such methods might be too complex for industry to adopt.…”