PSI - Issue 19

Jan Presse et al. / Procedia Structural Integrity 19 (2019) 423–432 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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5. Approach to estimate the fatigue life of adhesively bonded thin sheet connections

5.1. Experimental results

Since FESPRi provides accurate results for riveted thin sheet connections, the fatigue life of adhesively bonded connections needs to be estimated as well. The approach should be as easy to use and performable as FESPRi. The fatigue and linear-elastic behavior of each joint depends on several parameters. For adhesively bonded connections, possible parameters that affect the behavior are sheet thicknesses, the mechanical properties of the joined sheets and of the adhesive as well as the load condition. The dimensioning of the tested LS and CP specimens can be seen in Fig 1. To identify the impact of each parameter it was considered as a variant in the Design of Experiments (DOE). Table 1 shows the parameters and related ranges of the DOE for adhesively bonded connections. The parameter ranges are set around the earlier mentioned representative multi-material connections.

Table 1. Overview of DOE parameters for adhesive tests. Parameter Range Load cases

Lap Shear (LS) Coach Peel (CP) 0.9mm, 1.5mm EN AW-6016 DP600

Sheet Thickness

Materials

Adhesive Teroson EP5089 The tests of the resulting six combinations under cyclic loads were performed with a frequency of = 10 and a load ratio of = 0.1 . The failure criterion for both load configurations is set as separation.

10000

LS-DP600 LS-DP600-EN AW-6016 LS-EN AW-6016 CP-DP600 CP-DP600-EN AW-6016 CP-EN AW-6016

1000

100 Load amplitude F a [N]

10

1,0E+03

1,0E+04

1,0E+05

1,0E+06

1,0E+07

Cycles to failure N [-]

Fig 5. Fatigue test results for adhesively bonded connections.