Determination of diffraction elastic constants and residual stress in DED-Arc wall.

Arc Direct Energy Deposition (DED-Arc), also known as Wire Arc Additive Manufacturing (WAAM), is a form of additive manufacturing where fusible wire is melted by an electric arc and deposited along the desired path, offering a high deposition rate and the ability to create large near-net-shape metal components. This process involves differential heating and cooling, leading to significant residual stresses and distortions. The development of accurate and efficient residual stress modelling techniques is crucial to predicting the structural integrity and lifetime performance of DED-Arc components without relying solely on physical measurements, which have limited availability and are often expensive. Experimental benchmarks are used to acquire empirical data for validation of residual stress models, with neutron diffraction being the preferred method for measuring residual stress. Previous studies have also shown that the deposited material has reduced macroscopic stiffness, making the determination of diffraction elastic constants (DEC) essential for linking lattice strain to engineering stress. The proposed neutron diffraction experiment aims to determine the DEC for the SS316L material used in the DED-Arc wall and measure the residual stress distribution in the wall using neutron diffraction at the ISIS ENGIN-X beamline. The results will be used in the development of a benchmark for DED-Arc residual stress modelling and validation of new computational modelling techniques.