Abstract

The growth rates and activation energy for growth of thoria particles in thoria dispersion-strengthened nickel were measured after elevated temperature exposure. Growth was determined by direct measurement of thoria particle size on transmission electron micrographs. The thoria particles were distributed spatially in clusters in the hot consolitated alloy. Presence of particle clusters was found to provide the proper environment for a self-diffusion sintering-type particle coarsening. The rapid particle growth observed in this alloy form had too high a rate constant and too low an activation energy to constitute an Ostwald ripening mechanism, and was considered to reflect the grain growth stage of sintering. Further studies showed that thermomechanical treatments of hot consolidated material retarded this type of particle growth, by mechanically dispersing the ThO2 particle clusters.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.