PSI - Issue 13

Junji Sakamoto et al. / Procedia Structural Integrity 13 (2018) 529–534 Author name / Structural Integrity Procedia 00 (2018) 000 – 000

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Table 3. Stress distribution calculated from the simulation.

Normal distribution of stress calculated from the simulation 1  (68.3%) 2  (95.5%) 3  (99.7%)

10 G 30 G 70 G

45 MPa 143 MPa 454 MPa

91 MPa 287 MPa 907 MPa

136 MPa 430 MPa 1361 MPa

Fig. 8. S - N curve of aluminium alloy A5056 obtained by Patlan et al. (2001).

5. Conclusions

In this study, a multi-axial, random vibration test was performed on aluminium alloy A5056, and its fatigue fracture behaviour was analysed. Furthermore, we investigated whether the fatigue life of materials subjected to vibration can be predicted using the finite element analysis. Following are the conclusions drawn from this study: 1. The observation of the fracture behaviour and the observation of the fracture surface showed that a fatigue fracture occurred in the bending resonance mode regardless of the gravitational acceleration for the given size and shape of the specimens. 2. From the relationship between the time to failure and the gravitational acceleration, the time to failure was found to largely depend on the gravitational acceleration, though some other factors also influence the time to failure. 3. The fatigue life predicted using the finite element analysis was not inconsistent with the experimental result; this point requires further investigation in the future.

Acknowledgements

This work was supported by KAKENHI Grant Number JP17K14556. Authors would thank for the consortium of HALT-based high-quality design.

References

Tovo, R., 2002. Cycle distribution and fatigue damage under broad-band random loading. International Journal of Fatigue 24, 1137–1147. Dirlik, T., 1985. Application of computers in fatigue. Ph.D. Thesis, University of Warwick. Patlan, V., Vinogradov, A., Higashi, K., Kitagawa, K., 2001. Overview of fatigue properties of fine grain 5056 Al-Mg alloy processed by equal channel angular pressing. Materials Science & Engineering A 300, 171–182.