Mechanical Behaviour of Al 6061-T6 Aluminium Alloy Under Large Strain and Failure

Severe and extreme loads, that introduce large strains and failure, are a present challenge in the design of critical mechanical components. Even though full scale testing is a fundamental approach for reliable structural integrity evaluation, numerical simulation is an alternative economical method that is now increasingly chosen especially because of the development of computing performances. In particular, the numerical assessment of the ductile fracture in metallic components represents an innovative and challenging field in the structural integrity scenario. Aerospace, automotive and manufacturing industries have recently boosted their interest in these kinds of simulations with the aim to make these approaches, little by little, reliable also for certifications. Taking the requirement to characterize material for further impact simulations as a starting point, the work described in this chapter contains a complete characterization of the mechanical properties of Al 6061-T6 aluminium alloy as far as material hardening and fracture locus are concerned. The calibration has been carried out through a series of experimental tests on simple specimens. These specimens have similar geometry, but are subjected to different stress triaxiality, thanks to the use of a multiaxial hydraulic test machine. All the experimental tests have been numerically simulated and a complete material constitutive model has been calibrated, which based on the results of these experimental analyses.

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