Monitoring the precipitation of the hardening phase in the new VDM® Alloy 780 by in-situ high-temperature small-angle neutron scattering, neutron diffraction and complementary microscopy techniques

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F22%3A00564333" target="_blank" >RIV/61389005:_____/22:00564333 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1016/j.jallcom.2022.167203" target="_blank" >https://doi.org/10.1016/j.jallcom.2022.167203</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jallcom.2022.167203" target="_blank" >10.1016/j.jallcom.2022.167203</a>

Result language

angličtina

Original language name

Monitoring the precipitation of the hardening phase in the new VDM® Alloy 780 by in-situ high-temperature small-angle neutron scattering, neutron diffraction and complementary microscopy techniques

Original language description

The hardening phase precipitation process plays an important role in the development of new Ni-base superalloys. In the present work, we apply a powerful combination of complementary characterization techniques to characterize in-situ the gamma' precipitation in the new VDM (R) Alloy 780. During the whole heat treatment process, in-situ time-of-flight (TOF) neutron diffraction (ND) unambiguously identified the gamma' phase as well as its weight fraction and the misfit with the matrix while in-situ small-angle neutron scattering (SANS) provided precise precipitates' size analysis. Atom probe tomography (APT) and scanning electron microscopy (SEM) provided detailed microstructural characterization and chemical composition of the phases necessary for a proper neutron scattering data evaluation. This contribution reveals more de-tailed information on the nucleation, growth, and Ostwald ripening processes starting from the early precipitation stage in bulk samples using the complementary microstructure investigation methods. The nucleation and growth kinetics of precipitates at 720 degrees C depend on heating rates and the size distribution obtained in the pre-heating history of the sample. A subsequent heat treatment step at 620 degrees C, typically used in Ni-base superalloys, does not lead to similar progressive precipitation or growth. The expected matrix-diffusion-controlled Ostwald ripening process of the gamma' precipitates was in-situ monitored by SANS on a full precipitation hardened sample at expected operating temperatures (750 degrees C) showing slower coarsening kinetics than other reported Ni-based superalloys.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

20501 - Materials engineering

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Alloys and Compounds

ISSN

0925-8388

e-ISSN

1873-4669

Volume of the periodical

928

Issue of the periodical within the volume

DEC

Country of publishing house

CH - SWITZERLAND

Number of pages

14

Pages from-to

167203

UT code for WoS article

000879552400003

EID of the result in the Scopus database

2-s2.0-85132282453