PSI - Issue 77

C.F.F. Gomes et al. / Procedia Structural Integrity 77 (2026) 95–102 Gomes et al. / Structural Integrity Procedia 00 (2026) 000–000

97

3

Table 1. Tubular adhesive joints variables and respective dimensions.

Description

Dimensions [mm]

Overlap length, L O Adherends’ length, L S

10 20 40 45 50 60

Total length, L T

80 20

Outer diameter of inner adherend, d SI Outer diameter of outer adherend, d SE Thickness of inner adherend, t SI Thickness of outer adherend, t SE

24.4

2 2

Adhesive thickness, t A

0.2

2.2. Adherends and adhesives An aluminum alloy, a high-strength steel, and a CFRP were used as adherends. These materials were characterized in previous works (Campilho et al. 2005, Campilho et al. 2011, Valente et al. 2019), whose collected properties are depicted in Table 2 (directions 1, 2, and 3, used for the CFRP, denote the in-plane longitudinal, in-plane transverse, and out-of-plane directions, respectively). The adhesives’ properties are described in Table 3. The first adherend material, a structural aluminum alloy AW 6082-T651, having intermediate mechanical strength and excellent corrosion resistance, was also applied in the model validation. The second adherent material is the DIN 55Si7 steel. Due to its high strength, absence of plastic deformation enables the direct comparation of different adhesives without the adherends’ influence. The last material is the composite SEAL ® Texipreg HS 160 RM. This prepreg of epoxy resin reinforced with unidirectional carbon fiber presents high mechanical strength and high stiffness.

Table 2. Mechanical properties of the selected adherends (Campilho et al. 2005, Campilho et al. 2011, Valente et al. 2019).

Property

AW 6082-T651 DIN 55Si7 Texipreg ® HS 160 RM

E or E 1 [GPa]

70

210

109

E 2 [GPa] E 3 [GPa]

8.819 8.819 0.342 0.342 0.38 4315 4315 3200

0.33

0.3

ν or ν 12

ν 13 ν 23

G 12 [MPa] G 13 [MPa] G 23 [MPa]

- - -

- - -

261 324

1078 1600

- - -

σ y [MPa] σ f [MPa]

21

6

ε f [%]

Table 3. Collected properties of the AV138, 2015, and 7752 adhesives (Neto et al. 2012, Campilho et al. 2013, Faneco et al. 2017).

Property

Araldite ® AV138 Araldite ® 2015 Sikaforce ® 7752

Young’s modulus, E [GPa]

4.89 ± 0.81

1.85 ± 0.21

493.81 ± 89.6

Poisson’s ratio, ν b

0.35 a

0.33 a

0.33 a

Tensile yield stress, σ y [MPa] Tensile strength, σ f [MPa] Tensile failure strain, ε f [%] Shear modulus, G [GPa] Shear yield stress, τ y [MPa] Shear strength, τ f [MPa] Shear failure strain, γ f [%] Toughness in tension, G IC [N/mm] Toughness in shear, G IIC [N/mm]

36.49 ± 2.47 39.45 ± 3.18 1.21 ± 0.10 1.56 ± 0.01 25.1 ± 0.33 30.2 ± 0.40

12.63 ± 0.61 21.63 ± 1.61 4.77 ± 0.15 0.56 ± 0.21 14.60 ± 1.30 17.90 ± 1.80 43.90 ± 3.40 0.43 ± 0.02 4.70 ± 0.34

3.24 ± 0.5 11.49 ± 0.3 19.18 ± 1.4 5.16 ± 1.1 10.17 ± 0.6 54.82 ± 6.4 2.36 ± 0.2 5.41 ± 0.5 187.75 ± 16.4

7.8 ± 0.7

0.20 0.38

b

b

a Manufacturer’s data. b Estimated in reference (Neto et al. 2012).