2013 Volume 53 Issue 12 Pages 2250-2258
Failure criteria based on ductility associated with triaxiality are often used to define the strength of metal alloys as a function of the load modalities. However a discussion of the results with regards to the microstructural evolution and the behavior of the different phases is still not investigated, especially in multi-phase alloys. In this paper a ductile failure criterion was calibrated on α/β titanium alloy (Ti–6Al–4V). The applied approach is based on different experimental tests supported by numerical analyses carried out by detailed FE models. Specimens were tested on a multiaxial test system to investigate the failure induced by different states of stress triaxiality. Results have been discussed with regards to the textures induced in the lattice of the α-phase and β-phase, which are a direct consequence of the rotations associated with the dissipative plastic strains. Schmid factors at failure have been also calculated to determine which slip system have been activated by the different load modalities. The proposed approach could be also extended to steel.
