A modified Arcan test to analyze the behavior of composites and their assemblies under out-of-plane loadings

Abstract

Composite materials are a key element in weight reduction strategies, so the analysis of the mechanical behavior of assemblies of composite modules is of great importance. Failure initiation in bonded assemblies involving composites is often associated with crack initiation in the adhesive or delamination of the composite plies close to the adhesive joint, caused by interlaminar or throughthickness stresses. Thus, the analysis of the behavior of composites and their assemblies under outof-plane loadings is necessary in order to optimize such structures. However, few experimental devices are proposed in the literature and they often require thick composite specimens which are not representative of most industrial applications. This paper describes the use of a modified Arcan test to determine the behavior of composites and hybrid bonded assemblies over a wide range of tensileshear out-of-plane loadings. The key advantages of this fixture are the testing of thin composite plates and the use of an adhesive to fix samples. Moreover, an optimization of the design of the proposed device, based on finite element simulations, significantly limits the influence of edge effects in order to obtain accurate experimental results. Some test results are presented which underline the potential of the proposed approach.

3D Characterization of Mixed-Mode Fracture Toughness of Materials Using a New Loading Device

“…One of the most important problems is the specimen-fixture connection which causes bending or unwanted third mode loading conditions ( Figure 1). This problem had been mentioned by Hosseini et al (2008), Cognard et al (2011. In this research, in order to obtain reliable results of fracture parameters, correction factors of new designed fixture and modified Arcan fixture were determined using three-dimensional finite element analysis.…”

Determination of the 3D failure envelope of a composite based on a modified Arcan test device

“…Consequently, both the specimen geometry and the set fixation must be optimized in order to reduce these stress concentration. The current specimen geometry used in this study has been proposed by Cognard et al [17] and avoids the stress concentration in order to obtain reliable results (thanks to the grooves machined in the specimen see Fig. 1(c)).…”

“…It is based on the use of specimen manufactured from thin composite plates bonded to metallic substrates. It has already been shown that this method allows us to obtain reliable results [17]. In these previous works, the results were presented in terms of macroscopic failure envelope of the laminates.…”

A bifailure specimen for accessing failure criteria performance

“…Different modes are obtained with different loading angles, using a tensile testing machine. Along the years, many researchers have used Arcan's original or modified specimen [63,5,65,55,28,32]. Driemeier et al [31] proposed a modified Arcan specimen that can be tested at high or low triaxialities, depending the direction the specimen is loaded.…”