THE MEASUREMENT OF PRIOR PLASTIC-DEFORMATION IN METALLIC ALLOYS USINGTHE NEUTRON-DIFFRACTION TECHNIQUE

The neutron diffraction technique has been used to determine the exten t of prior plastic deformation in an aluminium alloy weld and preloade d cracked steel beams. The change in peak width has been shown to be a function of the prior plastic deformation, and is found to be insensi tive to the direction of prior straining, material and the orientation of the diffraction vector. Prior plastic deformation has also been sh own to influence the reference peak angle. The distributions of prior plastic strain in the steel cracked beam subjected to an overload were found to be in good agreement with results from finite element analys es.