Systematical analysis on the grain orientation evolution of pure nickel under plastic deformation by using in-situ EBSD

摘要

A combination of an in-situ tensile technique and electron backscattering diffraction (EBSD) was used to investigate the changes in microstructure and texture during plastic deformation of nickel with a high cubic texture. Surprisingly, unlike most data in the literature, it was found that the grains in nickel with a high cubic texture tended to align rather than scatter under a large force; thus, a large tensile stress causes enhancement of the cubic texture. The in-situ tensile tests are allowable to observe the entire process in real-time, while the EBSD results are helpful to separate texture changes at individual-grain resolution and to uncover the regular progression. It was found that, except for tiny grains and twins, most of the recrystallized grains tended towards the <001> pole. The only difference was that grains with a soft orientation effortlessly joined in the activation of the slip system, with the movement of dislocations playing a significant role in these grains. Conversely, the hard-orientation grains maintained the coordination of plastic deformation by means of rotation. Our results validate the in-situ tensile technique combined with EBSD as a systematic research method applied to the study of texture transformation for pure nickel.