Random Grain Boundaries Research Articles

Crack propagation in 〈110〉 oriented copper bicrystals with the Σ9 and random boundary

The role of a grain boundary (GB) in the fracture of metals has been a subject of interest and controversy for a long time. A dual effect of GB on crack initiation and propagation is still discussed. The GBs usually assist crack initiation and propagation. However, it can provide obstacle to the crack under certain circumstances. The purpose of the present work is to examine the effect of GB on fatigue crack propagation in copper compact tension (CT) specimens which allows one to control the crack initiation site and to observe crack growth on a relatively large area. Two kinds of bicrystals possessing a longitudinal planar {Sigma}9, A, or a random GB, B, were chosen in order to clarify the role of the GB structure.