In 1967, a review by Sherby and Burke concluded that 'creep of dispersion hardened alloys is poorly understood'. this view was endrosed in 1991 by Arzt, emphasizing that current theoretical treatments do not adequately model the creep characteristics displayed by oxidedispersion-strengthened (ODS) materials. For this reason, the research avenues pointed out by Sherby and Burke have been explored, seeking to identify approaches whic hrationalize and explain the complex creep behaviour patterns often observed for alloys strengthened by dispersions of fine precipitates or insoluble particle.s This analysis suggests that, while most recent theories have sought to model dislocation behaviour within crystals, it is necessary to recognize the different contributions made to the overall creep rate by the grain interiors and the grain boundary zones in polycrystalline materials. Furthermore, while dispersoids obviously impede dislocation movement during creep, the volume fractions of dispersoids typically present in ODS alloys are very low (approx 0.5 vol
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