Deformation and failure of carbon fiber composite specimens with embedded defects during tension-torsion test

Abstract

A need to timely reveal operational damages and technological defects requires a prompt control of states of structures made from composite materials and their consequent repairs aimed at service life extension. This work is devoted to the experimental study of inelastic deformation and fracture of specimens made from layer composite materials with prior introduced technological defects related to a possible inappropriate compacting and inappropriate bonding of material layers at a given restricted domain. The analysis is carried on the evolution of inhomogeneous deformation fields on the surface of carbon plastic specimens with an internal "delamination-type" defect under complex stress state. The method of active infrared thermography was used to identify the location and parameters of defects configurations. The obtained experimental data will be used for further tests related to sufficiency evaluation of signals received from the builtin sensors under complex loadings.Citation: Wildemann, V. V., Tretyakova, T. V., Strungar, E. M., Tretyakov, M. P., Deformation and failure of carbon fiber composite specimens with embedded defects during tension-torsion test, Frattura ed Integrità Strutturale, 46 (2018) 295-305.

Mechanical Properties Degradation of Fiberglass Tubes during Biaxial Proportional Cyclic Loading

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Experimental and Numerical Study of the Effect of the Presence of a Geometric Discontinuity of Variable Shape on the Tensile Strength of an Epoxy Polymer

“…Biocomposite materials can be used in different areas of applications, especially in light structures that have a bolted assembly before using. It is necessary to determine their mechanical properties through the different experimental techniques used under different types of loading such as traction [5][6][7], compression [8,9], torsion [10][11][12], fatigue [13][14][15] and impact [16]. The study of the geometry effect of the tensile specimens on the mechanical properties has gained importance from several authors.…”