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DOE OSTI · 2001067

Microstructural Investigation of Precipitation Treated A709 Test Samples

Zhang, Xuan
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Abstract

This report presents the microstructural characterization using scanning transmission electron microscopy (STEM) of two creep-tested ESR1150-PT specimens, one short-term and one long-term. The results show that during creep testing, the microstructure of the A709 ESR1150-PT material continues to evolve as expected due to the synergistic effect of strain, temperature and time. Key features include dislocation forest and cell structures, precipitates on grain boundaries, precipitates randomly within grains, and precipitates associated with dislocations. In addition, the STEM study of one ESR1100-SA specimen that has been tested to rupture at a relatively low temperature (550°C) for a relatively long term (16226 h) is also presented. The results show that there is a high density of very fine nano precipitates form on dislocations.

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36 MATERIALS SCIENCE

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Zhang, Xuan. 2023-09-01. Microstructural Investigation of Precipitation Treated A709 Test Samples. https://doi.org/10.2172/2001067

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36 MATERIALS SCIENCE↗