PSI - Issue 41

P.M.D. Carvalho et al. / Procedia Structural Integrity 41 (2022) 24–35 Carvalho et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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a)

b)

1.5

1.5

1.0

1.0

0.5

0.5

0.0

 y [MPa]

 y [MPa]

0.0

-0.5

-0.5

-1.0

-1.0

0

0.2

0.4

0.6

0.8

1

0

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0.8

1

x / L O [mm] SAJ 2015 SAJ 7752 DAJ 1/3 DAJ 1/8

x / L O [mm] SAJ 2015 SAJ 7752 DAJ 1/3 DAJ 1/8

Fig. 6.  y stresses for the different joint configurations with t P2 =1 (a) and t P2 =4 mm (b).

A significant difference is found between these two conditions, as for all joints with t P2 =1 mm the  y peak stresses are located close the curvature of the joint (near the symmetry plane), due to the compliance of the T-part and excessive deformations at this region. The increase of t P2 up to 4 mm progressively unloads these peaks and increases  y stresses at the free edge of the adhesive layer. In this case, the T- part’s high stiffness prevents the tip flexure and high stresses are generated. The magnitude of  y stresses also grow as t P2 increases. Between the different joint configurations, the highest  y peak stresses were found for the SAJ 2015, while the differences between the other configurations were nearly nil. In the DAJ, the transition regions between adhesives also cause slight  y stress disruptions. 3.2.2.2. Shear stresses  xy stresses are presented in Fig. 7 for t P2 =1 (a) and t P2 =4 mm (b). The direct comparison with Fig. 6 shows that the same loading causes  xy stresses of lower magnitude, when compared to  y , which was expected. On the other hand, this stress component appears due to the sliding between base and T-part, induced due to the joint deformation. The peak stress locations, and respective evolution with t P2 , agree with those of  y stresses, thus showing that  xy stresses are equally highly affected by the T- part’s stiffness. Different shear directions are also visible in the plots by the shift in sign of absolute  xy values.  xy peak stresses also increase with t P2 , and the SAJ 2015 configuration is critical, when compared to the identical behavior of the other configurations. Bigger differences along the adhesive layer are found for the DAJ configurations, with the  xy peak stresses at the transition regions instead of the overlap edges.

a) 1.5

b) 1.5

1.0

1.0

0.5

0.5

 xy [MPa]

 xy [MPa]

0.0

0.0

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-0.5

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-1.0

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1

x / L O [mm] SAJ 2015 SAJ 7752 DAJ 1/3 DAJ 1/8

x / L O [mm] SAJ 2015 SAJ 7752 DAJ 1/3 DAJ 1/8

Fig. 7.  xy stresses for the different joint configurations with t P2 =1 (a) and t P2 =4 mm (b).