3DStrainOrientationCalculator: a 3D diffraction data analysis tool for single-crystal substructure information extraction

Neutron diffraction is a crucial non-destructive technique for obtaining statistical information on the bulk properties of engineering materials. The program 3DStrainOrientationCalculator (3DSOC) is an innovative analytical tool designed to extract substructure information, including lattice strain and subgrain orientation, from single crystals (SCs) using monochromatic neutron diffractometer data. By separating subgrain diffraction via rocking curve analysis and employing 2D curve fitting on original diffraction data, 3DSOC accurately determines the diffraction intensity of individual subgrains while minimizing the impact of scanning step size on the final fitting results. It reduces the standard deviation of the fitting result's statistical error from the order of 10⁻³ to around 10⁻⁵. Additionally, 3DSOC extends its capabilities to the analysis of dual-phase SCs, where the lattice parameters of both phases are maintained with an accuracy of 10⁻⁴ nm, comparable to conventional methods. This study applies 3DSOC to SiC SCs and Ni-based SC superalloys, measured using two different diffractometers, and discusses the resulting improvements.