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Using a fatigue testing method by which fatigue cracks can be initiatedand propagated in a film adhered to cover a circular through-hole in a base platesubjected to push-pull cyclic loads, annealed rolled pure copper films of 100μmthickness were fatigued. The effects of microstructures such as crystal orientation dueto rolling and annealing twin boundaries on fatigue crack propagation behavior arestudied using two types of specimens that the rolling direction was parallel andperpendicular to the loading direction. The fatigue crack path showed larger zigzagpattern for the crack propagated toward the perpendicular direction to the rollingdirection than toward the parallel direction to the rolling direction and the fatiguecrack propagated slower toward the perpendicular direction to the rolling directionthan toward the parallel direction. After the fatigue testing, the crystallographiccharacteristic of rolling textures around the fatigue crack in the annealed film isanalyzed using EBSD (Electron Back-scatter Diffraction) system. As a result, theanisotropy of rolling texture remained after annealing and the annealing twinboundaries were inclined to orient to the rolling direction. The fatigue crack oftenpropagated along the annealing twin boundaries. Since the annealing twin boundarywas the same plane as the slip plane of the face-centered-cubic metal, the fatigue crackhad a tendency to propagate along the slip line initiated along the annealing twinboundary.