In the current world of advanced technologies, materials play a key role in our day-to-day life, and the investigation of their mechanical properties with the aim of improvement, thus becomes a matter of crucial importance. Nondestructive studies of microstructure and of internal stresses coupled with in situ mechanical tests and diffraction techniques yield an attractive tool for materials scientists. This assists not only to a growth of this topic in significance but also to its development into the detached and relatively new scientific field of diffraction analysis. Neutron diffraction used in the listed works of this book as a main probe for materials, has become the most powerful technique for examination of microstructure and mechanical properties, and it is therefore considered as a prerequisite. In response to the needs of diligent fabricator of materials, striving for the improvement of materials quality, the topic of internal stress development pertains to the significantly relevant issues covered by this book.