Functional gradation and its influence on damping behaviour of 51CrV4 steel

The simultaneous influence of both thermal and mechanical treatment was applied to produce a geometrically complex shaft from 51CrV4 steel. This special treatment led to the formation of adjacent microstructures, which were significantly different from each other. Specimens for structural studies and determination of mechanical and physical properties were cut from different locations on the produced shaft and tested in order to verify and understand the obtained functional gradation. It was found that the microstructural changes were accompanied by a change of mechanical and physical properties measured in terms of hardness, electrical resistivity, and internal friction. The Snoek–Köster peak was determined, and found to be strongly dependent on structure and dislocation density and their interactions with impurities.