Zhu, B; Leung, N; Kockelmann, W; Gorley, M; Whiting, M J; Wang, Y; Sui, T (2023) Neutron Bragg edge tomography characterisation of residual strain in a laser-welded Eurofer97 joint. Nuclear Materials and Energy, 36. 101462 ISSN 23521791

Preview

Text eid10372.pdf - Published Version Available under License Creative Commons Attribution. Download (14MB) | Preview

Abstract

Nuclear fusion is a potential source of electricity which can address the environmental problems posed by fossil fuels. Eurofer97 steel is a primary structural material for breeding blanket and divertor components in fusion Tokamaks. Assembling and maintaining the structural integrity of these in-vessel components requires remote joint techniques, such as laser welding, although it induces immersive residual stress. The interaction of the residual strain and the heterogeneous microstructure degrades the mechanical performance of fusion components. However, an inspection of bulk residual strain distribution is still challenging. This study presents the residual strain distribution in the bulk of the weldment using volumetric tomographic reconstruction. A neutron Bragg edge imaging technique is used to obtain 2D angular projections. The 3D volumetric strain map is reconstructed from 2D residual strain projections using the filtered back projection technique. It is found that the laser welding technique generates a uniform residual strain field in through-thickness direction. The results also demonstrate the potential of reconstructing volumetric residual strain distribution in bulk materials using fewer numbers of projections to reduce data redundancy and acquisition times for the neutron Bragg edge imaging technique.

Item Type:	Article
Keywords:	Neutron Bragg edge imaging, Strain tomography, Laser-welded Eurofer97 joints
Subjects:	Advanced Materials > Non-Destructive Testing
Divisions:	Materials and Mechanical Metrology
Identification number/DOI:	10.1016/j.nme.2023.101462
Last Modified:	08 May 2026 09:52
URI:	https://eprintspublications.npl.co.uk/id/eprint/10372