Fatigue damage in copper single crystals at room and cryogenic temperatures

Microscopic and microstructural analyses of fatigue damage evolution in copper single crystals vs temperature down to 4.2 K and environment revealed that the spacing between slip bands becomes smaller at lower temperatures and in inert environments whereas the thickness of a slip band decreases with the temperature but is independent of environment. The thickness of a slip band was found to correspond to the ladder rung spacing. Under all conditions, just initiated fatigue cracks are very short and small in depth.