疲労破面近傍のEBSD解析と塑性域観察

抄録

Characteristics of microstructures that are developed under fatigue fracture surface have been investigated from both EBSD analysis along fracture surface and slip-band observation. A fatigue crack growth test was conducted in a center-cracked tension specimen of polycrystalline copper. After the crack growth test, specimen surface was first observed with a SEM to examine morphology of the slip bands emerged at grains adjoining to the fracture surface. Then, the observed grains were milled by a FIB to obtain tiny flat planes parallel to the fracture surface. The flat planes were analyzed with the EBSD system to estimate local lattice rotation. In the grains showing the slip bands of single slip, large lattice rotation was detected by the EBSD analysis. However, the lattice rotation was relatively suppressed in the grains showing multiple slips at the surface.