document: The displacement cascade is a rapid process (of order picoseconds). Further migration of vacancies and SIAs, mainly by diffusion, happens over a timescale of order nanoseconds [17]. This is still short compared to operating times, so is important to consider the equilibrium result of such processes: If the vacancies and SIAs were likely to find their Frenkel partner, recombine, and annihilate, then the metal should essentially return to its original structure; however, if defects instead formed large clusters of a single type this could result in formation of voids, dislocation loops or swelling, possibly weakening the material in the process. Defects can be trapped at grain boundaries or surface, so for an ODS particle to effect the diffusion, there concentration must be such that there are many such particles in each grain.
doc_bio_tags: O B I O O O O O O O O B I I I I O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O B O O O O O O O O O O O O O O B B I O B O O O O O O O B O O O O B O O O O O O B I O O O B O O O O O O O O O O O O O B
extractive_keyphrases: defects diffusion dislocation loops displacement cascade grain migration of vacancies and sias ods particle structure swelling voids