Monday  |  Lakeshore C  |  12:00 PM–12:20 PM

#19786, Mapping Full Stress Tensors in Advanced Manufactured Additive Friction Stir Deposition 7075 Aluminum

Neutron diffraction for the purpose of residual strain mapping has become a readily utilized technique for the purpose of model validation in engineering materials. However, due to experimental constraints neutron diffraction typically maps the residual strain of a polycrystalline material in three orthogonal directions, assuming these orthogonal directions are principal strains. This assumption neglects the effects of shear strain and the possibility of the principal strains to vary throughout a component spatially. Additionally, sample geometry can limit directions of strain which are measurable due to long neutron path length. This research will show utilization of a generalized least squared analysis on neutron diffraction data where the measurements are taken at various rotations of the measurement gauge volume to map a full strain tensor. The neutron diffraction measurements were taken at the HIDRA Instrument at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). The full strain tensor can show effects due to rotations of the principal strains in the component. Also, this method will allow for measurement of stress in a complex additive component made via Additive Friction Stir Deposition (AFSD), a process in which shear deformation controls.

Jeff Bunn   Oak Ridge National Laboratory
Cole Franz   University of Tennessee
Lauren Miller   University of Tennessee
Benjamin Wing   University of Tennessee