PSI - Issue 28

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Vinicius Carrillo Beber et al. / Procedia Structural Integrity 28 (2020) 1950–1962 V.C. Beber and M. Brede / Structural Integrity Procedia 00 (2019) 000–000

1958

The hindering of the lateral contraction and the higher values of the Poisson’s ratio could explain this behaviour. In this regards, elastic adhesives are relatively more sensitive to loadings inducing hydrostatic stresses than structural adhesives (Wulf et al., 2017), which explain the relative lower strength of butt and scarf joints of elastic adhesives .

Figure 7 - Static tests: (a) static strength of adhesive joints, (b) ratio of elastic and structural adhesive joint strength

Figure 8 - FE Analysis: stress multiaxiality distribution of butt, scarf and TAST joints for structural (left) and elastic (right) adhesives considering a nominal stress of 1 MPa

4.2. Fatigue Testing

The results of fatigue tests in the form of SN curves are presented in Figure 9 for the butt, scarf and TAST joints: (a) for structural adhesives, and (b) elastic adhesives. The fatigue strength of butt joints was the highest, followed by the scarf joints, and TAST joints for both adhesives. Another important aspect from SN curves is the steeper slope of TAST joints, which could be associated with the presence of stress concentrations at the overlap ends of TAST joints