April 23rd
when: Tuesday 23/4/2019, 13:00
where: KE E-541 (møterom)
speaker: Sandra Cabeza (Institut Laue-Langevin, Grenoble, France)
title: Neutron stress characterization for engineering components at SALSA – ILL
abstract:
SALSA, the “Stress Analyser for Large Scaled engineering Applications”, is a stress diffractometer dedicated to engineering sciences and industrial R&D. It is part of the instrument suite of the Institut Laue-Langevin (ILL) in Grenoble, France, which operates the most intense neutron research steady source in the world.
The non-destructive determination of residual stresses within engineering components using laboratory equipment is limited to the surface (X-ray) or near surface regions (Barkhausen-noise). The neutron technique is based on diffraction at (poly-) crystalline material, comparable to x-ray diffraction, but permits much higher penetration. Bulk stress investigations are often carried out using destructive methods (i.e. deep-hole drilling, slicing or the contour method), which are based on the relaxation of stresses and therefore limit further materials investigations, including the destruction of an expensive, highly elaborated part. Neutron stress determination is a non-destructive technique, applicable to mock-ups as well as realistic sized engineering components. It allows mapping of stress fields from the bulk of the work piece to its near surface with adjustable lateral resolution, providing a 3D map of the full stress tensor. Neutron techniques are well suited for in-situ or in operando investigations, using even complex sample environment. Furthermore, the non-destructive character allows the investigation of complete development cycles since the same sample can be measured repetitively, after it has received further treatment or aging tests.
The new policy at SALSA with 50% beam time dedicated to industry is disclosed as strategy towards societal impact and sustainability of neutron stress determination. Particular examples of Friction Stir Welding in Aerospace, Additive Manufacturing and Casting processing developments will be presented.