Publication detail

Atomic resolution characterization of strengthening nanoparticles in a new high-temperature-capable 43Fe-25Ni-22.5Cr austenitic stainless steel

HECZKO, M. ESSER, B. SMITH, T. BERAN, P. MAZÁNOVÁ, V. MCCOMB, D. KRUML, T. POLÁK, J. MILLS, M.

Original Title

Atomic resolution characterization of strengthening nanoparticles in a new high-temperature-capable 43Fe-25Ni-22.5Cr austenitic stainless steel

Type

journal article in Web of Science

Language

English

Original Abstract

Advanced scanning transmission electron microscopy (STEM) was used to study two distinct populations of nanoparticles associated with the extraordinary strengthening of the highly-alloyed austenitic stainless steel Sanicro 25 during cyclic loading at 700 °C. Fully coherent and homogeneously dispersed Cu-rich nanoparticles precipitate rapidly as a result of thermal exposure, along with nanometer-sized incoherent NbC carbides that nucleate on dislocations during the cyclic loading at high temperature. The atomic structure of nanoparticles was investigated by probe-corrected high-angle annular dark-field STEM imaging. Compositional analysis of the nanoparticles was conducted using high spatial resolution energy dispersive X-ray spectroscopy combined with electron energy-loss spectroscopy. Experimental observations were validated by image simulations of the Moiré-like contrast exhibited by NbC carbides. The important role of both nanoparticle populations for the overall cyclic response is discussed. As a result of pinning effects and associated obstacles, dislocation motion is significantly retarded preventing formation of substructures with lower stored internal energy. With recovery heavily suppressed, forest dislocation strengthening supported by precipitation and solid solution hardening, leads to the remarkable increase of cyclic strength at elevated temperatures.

Keywords

Scanning transmission electron microscopy; Austenitic stainless steel; High temperature; Fatigue; Strength; Nanoparticles

Authors

HECZKO, M.; ESSER, B.; SMITH, T.; BERAN, P.; MAZÁNOVÁ, V.; MCCOMB, D.; KRUML, T.; POLÁK, J.; MILLS, M.

Released

14. 3. 2018

Publisher

ELSEVIER SCIENCE SA

Location

PO BOX 564, 1001 LAUSANNE, SWITZERLAND

ISBN

0921-5093

Periodical

Materials Science and Engineering A

Year of study

719

Number

1

State

Swiss Confederation

Pages from

49

Pages to

60

Pages count

11

URL

https://www.sciencedirect.com/science/article/pii/S0921509318301862

BibTex

@article{BUT150954,
  author="Milan {Heczko} and Bryan D. {Esser} and Timothy M. {Smith} and Přemysl {Beran} and Veronika {Mazánová} and David W. {McComb} and Tomáš {Kruml} and Jaroslav {Polák} and Michael J. {Mills}",
  title="Atomic resolution characterization of strengthening nanoparticles in a new high-temperature-capable 43Fe-25Ni-22.5Cr austenitic stainless steel",
  journal="Materials Science and Engineering A",
  year="2018",
  volume="719",
  number="1",
  pages="49--60",
  doi="10.1016/j.msea.2018.02.004",
  issn="0921-5093",
  url="https://www.sciencedirect.com/science/article/pii/S0921509318301862"
}