PSI - Issue 25

Daniel J. Cruz et al. / Procedia Structural Integrity 25 (2020) 316–323

322

Daniel J. Cruz et al. / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 9: Strain field distribution for both compression (step 1) and tension (step 2)

5. Conclusions

This article reports the development of mini-tensile equipment for sheet metal mechanical characterisation - Mini Sample Tester Device (MSTD) using the Digital Image Correlation (DIC) as the method to evaluate the strain distri bution in the specimen plane. First, some preliminary tests in a first equipment were performed to evaluate the behaviour of di ff erent geometries of specimens in a mesoscale. The obtained curves have the same shape as in the case of a standard tensile test thus showing that miniaturised specimens are a powerful technique for sheet metal mechanical characterisation. The utility of Digital Image Correlation technique for meso-scale tests was confirmed. Afterwards, having in consideration this preliminary tests, the MSTD was developed. The maximum capacity of this equipment is 2.5 kN and its maximum stroke is 42.7 mm. The equipment is capable to test specimens in tension and compression loadings. Finally, some cyclic tests were performed in the new equipment to evaluate the potentiality of the MSTD. The results obtained were very satisfying because it was possible to reach plastic strain both in compression and tension.

Acknowledgements

The authors gratefully acknowledge the support of the DEMec and the SMPT and the financial support under the projects P2020-PTDC / EMS-TEC / 6400 / 2014 (POCI-01-0145-FEDER-016876), POCI-01-0145-FEDER-031243, POCI-01-0145-FEDER-030592, POCI-01-0145-FEDER-032466, co-financed by Competitiveness and International isation Operational Program (Compete2020), through the European Regional Development Fund (FEDER) and by the Foundation for Science and Technology (FCT) through its State Budget component.

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