The transmission spectrum of thermal neutrons through a polycrystalline sam
ple displays sudden, well-defined increases in intensity as a function of n
eutron wavelength. These steps, known as Bragg edges, occur at the point at
which the neutron wavelength exceeds the Bragg condition for coherent scat
tering from the respective lattice planes, and can be easily observed using
the time-of-flight method. Accurate location of these edges and determinat
ion of their magnitude and shape can be used to extract information about t
he stress state, texture and phases present in the material. This paper des
cribes a method for analysing these edges singly and collectively, using a
Pawley-type refinement. Furthermore, experimental trials are presented whic
h demonstrate the utility of the method for the accurate measurement of lat
tice spacings, and thus strain. These trials include measuring the lattice
parameter in Cu/Zn alloys as a function of Zn content, and the determinatio
n of elastic strain of an iron rod under tensile/compressive straining. In
the former case the results are compared with Bragg diffraction peak measur
ements made on HRPD and in the latter case with conventional strain gauge m
easurements.