Optimisation of Data Collection and Processing for Efficient Strain Scanning

Article type: Research Article

Authors: Webster, P.J. | Kang, W.P.

Affiliations: Institute for Materials Research, School of Aeronautical, Civil and Mechanical Engineering, University of Salford, Salford, M5 4WT, UK

Note: [] Corresponding author.

Abstract: A constraint to the academic and industrial exploitation of neutron strain scanning is its cost in relation to that of alternative techniques. Generally, a large proportion of the resource cost is that for beam-time. The efficient utilisation of beam-time can be enhanced by optimising data collection and processing. The selection of three principal related factors — detector range, angular step size and the counting time — determines the data quality and uncertainties in defining the Bragg peak parameters required to determine strain. Theoretical and numerical analysis of computed and experimental data are used to establish a general set of well-founded, semi-empirical but theoretically-based, practical “rules of thumb” to be used when making strain measurements to a specified statistical uncertainty. The “rules” apply mostly to constant wavelength techniques where the angular position and other profile parameters of a single symmetrical Bragg peak are required but have relevance for fixed angle time-of-flight methods.

Keywords: Strain scanning, Strain uncertainties, Numerical analysis, Peak fitting, Optimisation, Diffraction

DOI: 10.1080/1023816022000006207

Journal: Journal of Neutron Research, vol. 10, no. 2, pp. 93-110, 2002