Evidence of extinction in strongly textured high-purity copper

In order to test the influence of extinction on texture measurements, pole figures of four copper samples were measured using neutron diffraction with three different wavelengths. The copper samples had previously been cold rolled to different extents and partially annealed. Therefore, three of the samples presented a relatively strong texture and the fourth sample a relatively weak texture. In this study, the results from equivalent pole figures were compared between the different samples. These investigations showed that, in general, except for the sample with weak texture, the 222 reflection showed higher pole density maxima than the 111 reflection. Since all measuring conditions were the same for both reflections, this difference was attributed to extinction. The pole density maxima of strong reflections also revealed a slight tendency to lower values with decreasing wavelengths. This phenomenon is attributed to the fact that more reflections exist at shorter wavelengths and therefore an increase in secondary extinction is measurable at these wavelengths.