PSI - Issue 41

J.E.S.M. Silva et al. / Procedia Structural Integrity 41 (2022) 36–47 Silva et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 8 – SDEG at P m in the adhesive layer.

4.4. Failure modes and joint strength Most of the simulated TSJ failed cohesively in the adhesive layer, except for  =3.43°. For this joint configuration, the adherends plasticized and the full adhesive strength was not reached. Fig. 9 shows the graphic visualization of the equivalent plastic deformation (PEEQ) for the joint with  =3.43° at the instant of P m . Fig. 10 shows the graphic visualization of the PEEQ for the joint with α =45°, at the same instant, showing no signs of adherend damage.

Fig. 9 – PEEQ graphic visualization in the TSJ with  =3.43°.

Fig. 10 – PEEQ graphic visualization in the TSJ with  =45°.

From the evaluation of the P -  curves in Fig. 11, it is possible to compare P m of the TSJ between the different  . Decreasing  essentially increases the stiffness and P m , with emphasis on P m due to the exponential shear area increase with the  reduction (He et al., 2010). On the other hand, reducing  also diminishes  y stresses which negatively affect adhesive joints and lead to their premature failure (Petrie, 2000). The adhesive analysed shows high specific P m for each  (i.e., averaged over the bond area) and a linear behaviour until failure. As an adhesive of moderate ductility, it enables an improved stress distribution which consequently favours joint strength (Campilho et al., 2013). However, as shown in Fig. 11, P m for the TSJ with  =3.43° was limited by the adherends’ plasticization, leading to a constant P up to the aluminium failure. For  ≤ 10°, failure in the adhesive layer leads to an abrupt drop of P up to adherend separation.