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

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 coefficient R, leads to an intensity correction factor that can be approximated quite well by another March function, with coefficient R^-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.