The December 1998 issue of the BCA Newsletter contained a nine page CLRC report on users meetings and instrument improvements from the Daresbury and Rutherford laboratories combined with information on protein and materials application, new stations, and new detectors and the ever increasing demand for access to the facilities.

Measuring stress with neutrons. The measurement of stress using neutron diffraction is a rapidly growing field, of great relevance both to the academic materials science world and to the industrial world of structural engineering. Recent efforts to introduce an international standard for neutron stress measurement, coupled with European Union funded ventures to bring the technique to a broader range of industries are stimulating an increasing interest in the technique.

Increasing demand and international standards. Industrial demand has led to two European funded networks with members from industry, academia and neutron facilities. RESTAND, a network run by the JRC in the Netherlands aims to establish best practices for neutron measurements. TRAINSS, a network run by ISIS in the UK, aims to introduce industries to the technique and train them in measurement practice and interpretation.

The VAMAS TWA20 initiative, headed by Imperial College, London, is made up mostly of academics and representatives from facilities around the world; it is working to define an international standard for stress measurement using neutrons. The project will involve four different round robin samples which will be measured at each neutron facility. Each is typical of a problem found in real measurements: high strain gradients, multiple phases, through surface strain measurements, and large compositional variations. A training network has been proposed to help cope with the increasing demand from academic users. This will allow novice users to accompany more experienced ones on experiments at neutron facilities where they will learn by example, helping with the experiments and discussing the results and their interpretation. Help with proposal writing will also be given.

Anyone interested in using neutrons for stress measurement, or any other applied applications, is encouraged to contact M. Daymond, email: mark.daymond@rl.ac.uk. Tel: 4401235 445414.

From BCA Newsletter, December 1998