PSI - Issue 18

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V. Dattoma et al. / Procedia Structural Integrity 18 (2019) 719–730 Author name / Structural Integrity Procedia 00 (2019) 000–000

721

Each laminate is composed by 16 plies symmetrically arranged in angle-ply configuration. The lamination sequence is [+45, -45,0,90] 2s . The laminates are connected through a rivet at specific clearance values, as measured on inspected specimens before tests. The fastening system is basically a threaded high-lock aeronautical bolt which combines a rivet and bolt behavior. It consists of two parts, a threaded pin and a special collar. In this work, the composite was realized through the Liquid Resin Infusion process. The main characteristics of the fibers and the matrix used are shown in Table 1. Table 2 shows the mechanical properties of the material used for the riveted bolt. Table 1. Mechanical and physical properties of CFRP constituents. fibre properties matrix properties E 11 (GPa) 290 E 11 (GPa) 3.4 E 22 (GPa) 14 E 22 (GPa) 3.4 G 12 (GPa) 25 G 12 (GPa) 1.24 G 23 (GPa) 7 T g (°C) 179 ν 12 0.236 ν 12 0.43 ν 23 0.011 ν 23 0.43 ρ (g/cm 3 ) 1.785 ρ (g/cm 3 ) 1.24

Table 2. Mechanical Properties of Ti6Al4V. Mechanical properties Modulus of Elasticity

113.8 [GPa]

Shear modulus Poisson’s Ratio

44 [GPa]

0.342

Tensile Strength, Ultimate Tensile Strength, Yield Compressive Yield Strength

950 [MPa] 880 [MPa] 970 [MPa]

3.2. Test methods Mechanical bearing tests have been carried out on a servo hydraulic testing machine INSTRON 8850 having a load capacity of 250 kN in the Experimental Mechanical Laboratory at the University of Salento (Lecce, Italy).

(a) (b) Fig. 2. (a) Experimental setup of Bearing single shear ASTM D5961-B; (b) experimental steel support for specimen bearing test;