PSI - Issue 83

R.J.B. Rocha et al. / Procedia Structural Integrity 83 (2026) 187–195

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the PLA and PETG samples and an Ender 6 to produce the ABS test coupons. The selection of printing parameters per material was based on previous published investigations and is detailed in Table 1. The results of the mechanical properties of the three adherends, PLA, PETG and ABS, obtained through experimental tensile test campaign, are detailed in a previous published work (Ribeiro et al. 2025).

Table 1. PLA, PETG and ABS printing parameters.

Material

PLA

PETG

ABS

Printer model and make Adhesion table type

Ender 3 Max Carborundum

Ender 3 Max Carborundum

Ender 6

Carborundum

Adhesion table temperature [°C] Extruder nozzle temperature [°C] Material deposition speed [mm/s] Extruded line thickness [mm] Outer wall thickness [mm] Bottom and top shell thickness [mm] Extruded filament thickness [mm] Layer height [mm]

60

80

70

215 75 0.2 0.4

230 75 0.2 0.4

230 120 0.2 0.4

1.2 (3 lines)

1.2 (3 lines)

1.2 (3 lines)

0.8 0.4

0.8 0.4

0.8 0.4

Infill pattern Infill density [%]

Lines

Lines

Lines

50

50

50

Build plate adhesion type

Skirt

Skirt

Skirt

The selected adhesives were the Araldite ® 2015 and the Sikaforce ® 7752 FRW L60. The Araldite ® 2015 presents high strength and stiffness, whereas the Sikaforce ® 7752 shows a more ductile and flexible behaviour, although being less strong. The mechanical and fracture properties of the adhesives were characterized in previous published works and are detailed in Table 2.

Table 2. Mechanical and fracture properties of the adhesives (Campilho et al. 2013, Faneco et al. 2017).

Properties

2015

7752

Young’s Modulus, E [GPa]

1.85 ± 0.21

0.49 ± 0.09

Poisson’s Ratio, ν *

0.33

0.30

Yield Tensile Strength, σ y [MPa] Ultimate Tensile Strength, σ f [MPa] Tensile Strain at failure, ε f [%] Transverse Elastic Modulus, G [GPa] Shear Yield Strength, τ y [MPa] Shear Ultimate Strength, τ f [MPa] Shear Strain at Failure, γ f [%] Tensile Toughness, G Ic [N/mm] Shear Toughness, G IIc [N/mm]

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 ± 0.48 11.48 ± 0.25 19.18 ± 1.40 0.19 ± 0.01 5.16 ± 1.14 10.17 ± 0.61 54.82 ± 6.38 2.36 ± 0.17 5.71 ± 0.47

* Supplier data

2.2. Geometries and experimental conditions SLJs and SJs were investigated using FDM adherends (Fig. 1). The main geometric parameter under analysis is the overlap length ( L O ), which varies between 5 and 20 mm, while all other joint dimensions were maintained unchanged.

a)

b)

Fig. 1. Geometry and dimensions of: SLJ (a) and SJ (b).