NANOSTRUCTURE CHARACTERIZATION OF IN738LC SUPERALLOY FATIGUED AT HIGH TEMPERATURE

0399770 - ÚFM 2014 RIV CZ eng C - Conference Paper (international conference)
Petrenec, M. - Strunz, Pavel - Gasser, U. - Heczko, Milan - Zálešák, J. - Polák, Jaroslav
NANOSTRUCTURE CHARACTERIZATION OF IN738LC SUPERALLOY FATIGUED AT HIGH TEMPERATURE.
NANOCON 2013 Conference Proceedings. Ostrava: Tanger, 2013, art. no. 2001. ISBN 978-80-87294-44-4.
[NANOCON 2013. International Conference /5./. Brno (CZ), 16.10.2013-18.10.2013]
R&D Projects: GA ČR(CZ) GAP204/11/1453; GA MŠMT(CZ) ED1.1.00/02.0068; GA MŠMT LM2011019
Institutional support: RVO:68081723 ; RVO:61389005
Keywords : superalloys * nano-precipitation * neutron scattering * STEM detector * TEM
OECD category: Audio engineering, reliability analysis

The nanostructure of Inconel 738LC Ni-superalloy strengthened by trimodal γ’ precipitates distribution was investigated after Low Cycle Fatigue (LCF) loading at temperature 700°C. Different microscopic techniques as Scanning Electron Microscope (SEM) equipped with STEM detector, transmission Kikuchi diffraction in the SEM, transmission electron microscope (TEM) in the bright field mode and high resolution transmission electron microscopes in STEM mode were used for the characterization of nanostructure. The characteristic morphology of γ’ precipitates was examined by ex-situ and in-situ Small Angle Neutron Scattering (SANS) at high temperatures. All microscopic techniques indicate that the morphology of γ’ precipitates distributed in the γ matrix as received state corresponds to two types, i.e. large cuboid-like precipitates with the size around 670 nm, and the spherical precipitates with the diameter 52 nm. After the LCF tests at temperature 700°C, the ex-situ SANS measurement yielded additional scattering intensities coming from another small γ’ precipitates with estimated size up to 10 nm.
Permanent Link: http://hdl.handle.net/11104/0226982