Microstrain Measurement in Plastically Deformed Austenitic Steel

摘要

Some results of high-resolution neutron diffractionexperiments resulting in determination of the microstrain inmetallic materials are reported. The method of the diffraction linebroadening analysis was verified in two materials, investigatedearlier by X-ray diffraction: an austenitic steel prestrained up to 30precent and a cold rolled aluminium magnesium alloy. For thesematerials, the mean-square microstrain and the dislocation densitywere determined, a good agreement was reached with the results ofX-ray experiments. As an application of such analysis weinvestigated the influence of the shot-peening treatment on anaustenitic steel. This treatment is commonly used to introducecompressive stresses in the surface of material, giving improvedresistance to fatigue fracture. The microstrain distribution and thesize of coherently diffracting blocks for a shot-peened sample ofaustenitic steel as a fundction of depth from the surface aredetermined by the above analysis and the results are presented.