Preferred orientation in Debye–Scherrer geometry: interpretation of the March coefficient

Abstract

The March function is a widely used preferred-orientation correction function that, in flat-plate geometry, often closely approximates the pole-density profile of axially symmetric textures. It is shown that in Debye–Scherrer geometry, the assumption that the pole-density profile of a powder specimen can be described by a March function with coefficientR, leads to an intensity correction factor that can be approximated quite well by another March function, with coefficientR−1/2. This result validates the use of the March function correction in Debye–Scherrer geometry, facilitates the comparison of results obtained in the different geometries and should prove useful in some studies of axially symmetric textures and in residual-stress analysis.