1st European Mechanics of Materials Conference on Local Approach to Fracture '86 - 96'
J. Phys. IV France 06 (1996) C6-101-C6-111
The Influence of the Back Stress (X) and the Hardening Rate (dX/Xεpqe) on Void Nucleation in α/β Titanium AlloysA.L. Helbert, X. Feaugas and M. Clavel
Université de Technologie de Compiègne, Division Mécanique, Laboratoire LG2mS, URA 1505 du CNRS, BP. 649, 60206 Compiègne cedex, France
The study of void nucleation in four α/β titanium alloys has provided nucleation criteria corresponding to voids at the α/β interface. This macroscopic nucleation criterion, written as ∑m=f(εpqe), was explained with the help of microscopic observations. Microscopic parameters such as plastic strain in the α-phase or local hydrostatic stress σm at the α/β interface have been linked to the damage initiation. Besides, the influence of the different heterogeneity levels on the macroscopic nucleation criterion was demonstrated using the macroscopic mechanical parameters : back stress (X) and hardening rate (dX/Xεpqe) which express the plastic strain incompatibilities and their evolution in such alloys.
© EDP Sciences 1996