Abstract
The bending fatigue tests were performed using the micro-cantilever-shaped specimens of AZ31 magnesium alloy fabricated by the focused ion beam (FIB) processing to investigate the effects of the scale and the grain orientation on the fatigue behavior. The configuration of specimen was the rectangular cross section of 3μm × 8μm and the height of 40μm. For the fatigue test of micro cantilever specimens, the fatigue testing apparatus was constructed using the piezo actuator and the high resolution microscope for controlling the very small displacement. Before fatigue tests, crystallographic orientations of the specimens were analyzed by EBSD technique. The micro cantilever specimens exhibited the higher fatigue strengths than the bulk-sized ones. The fatigue strengths of micro cantilever strengths were strongly affected by the crystallographic orientations. When basal slips mainly operated, fatigue lives were the shortest. But the operation of non-basal slip systems resulted in the longer fatigue lives, where Schmid factors of basal slip systems were very low.
