Etude radiocristallographique de l'orientation preferentielle des depots electrolytiques de nickel
Résumé
A quantitative X-ray analysis is made of the fiber texture exhibited in nickel electrodeposits. Pole figures are built thanks to a simple reflection diffractometer method without a texture goniometer, and corrected throughout the comparison with a random-oriented nickel sample, the randomness of which is carefully discussed.
The experimental correction factor is found to depend on the grain size of the random-oriented sample and not to be in agreement with the theoretical prevision.
Assuming that pole distributions are gaussian near the fiber axis, three parameters are defined which thoroughly determine the preferred orientation.
An illustration of this method is given with nickel electrodeposits obtained from a Watts bath in well-defined conditions of preparation. Several deposits exhibiting a [311] pseudotexture are shown to possess in fact a [211] preferred orientation with broadly-dispersed pole distributions.