PSI - Issue 19

Shinji Hashimura et al. / Procedia Structural Integrity 19 (2019) 204–213 Author name / Structural Integrity Procedia 00 (2019) 000–000

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5. FE analysis 5.1. FE Model and boundary conditions

Elasto-plastic analysis was conducted in axisymmetric two dimensional analysis in order to verify the cause of kink for A6056 bolt in Haigh diagram. Figure 7 shows an illustration of the FE analysis model of the bolted joint. FE analysis was conducted using ANSYS 17.0. This model is simulating the bolted joint including two clamped parts. The grip length of bolted joints was l g =32 mm. The radius of the root of the thread and of the incomplete thread was faithfully reproduced the actual test bolts. The axis of bolt was constrained in x direction. The bottom surface of clamped part A was constrained in y direction as shown in Fig. 7. The upper surface of clamped part B was pulled by the mean load Q m in the y direction and then cyclic load Q a was applied ten cycles. Table 4 shows the mechanical properties of aluminum alloy A5056, A6056 and steel for FE analysis. The material of clamped part A and B was complete elastic body simulating steel and Young's modulus was E =206 GPa and Poisson's ratio was ν = 0.3. Young's modulus for A5056 bolts was E =72 GPa, Poisson's ratio was ν =0.33. 0.2 % proof stress was  0.2 =268 MPa and the strain hardening coefficient was H =6.0 GPa. Incidentally, 0.2 % proof stress  0.2 in Table 4 is different from  0.2 in Table 1.  0.2 in Table 1 is 0.2 % proof stress as a bolt. Whereas  0.2 in Table 4 was 0.2

Fig. 7 FE analysis model of the bolted joints.

Table 4 Material properties for A5056 bolt and A6056 for FE analysis

0.2 % proof stress of material  0.2

Strain hardening coefficient H

Young's modulus E

Poisson's ratio ν

Materials

A5056 for bolt and nut A6056 for bolt and nut Steel for clamped part

72 GPa 72 GPa 206 GPa

0.33 0.33

268 MPa 358 MPa

6.0 GPa 72 MPa

0.3

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