Two-dimensional analysis of void growth and linkage during deformation

Ductile fracture by void nucleation, growth and coalescence is a stochastic event among which the final coalescence stage is the least understood. By fabricating model materials with pre-existed voids, the growth and coalescence events were extracted. In this study, the experiments was performed on pure copper and α-brass. Foil samples were machined with laser drilled holes in the gauge section. In situ tensile test was adopted to capture the void growth and linkage processes. Quantitative data were gathered i.e., the longitudinal and lateral length of voids and the intervoid spacing, etc. From this study, the effect of void orientation on coalescence strain was investigated. By comparing with the classic model, we found that the existing models for void coalescence turned to be invalid when voids are not aligned normal to the tensile direction. And a modified Thomason model was also been discussed. Copyright © 2013 MS&T'13®.