Surface integrity after turning a duplex stainless steel with respect to tool geometry

Abstract

This study deals with surface integrity expressed in terms of stress state as well as microstructure alterations after turning a duplex stainless steel. Residual stresses and the presence of strain-induced martensite are studied as functions of the rake angle. Residual stresses of surface and sub-surface layers were determined by the use of the X-ray diffraction and hole-drilling techniques. X-ray diffraction enables us to distinguish between residual stresses in each phase separately, which is not possible when the hole-drilling method is applied. Furthermore, alterations in the near surface region are also analysed by the use of the magnetic Barkhausen noise and metallographic observation.