Publication detail

Oxidation Behavior and Outward Diffusion of Al Along Oxide Grain Boundaries of FeCrAl Alloys Overdoped with Zr and Hf

DARADKEH, S. MOUSA, M. SOBOLA, D.

Original Title

Oxidation Behavior and Outward Diffusion of Al Along Oxide Grain Boundaries of FeCrAl Alloys Overdoped with Zr and Hf

Type

journal article in Web of Science

Language

English

Original Abstract

The formation of the alpha-Al2O3 scale on reactive element (RE)-doped FeCrAl alloys is commonly believed to be primarily caused by inward oxygen transport along grain boundaries. However, this study suggests that metal ion outward diffusion also plays a role in the development of the oxide scales and their microstructural characteristics. The study examines the oxidation behavior and grain boundary outward diffusion of iron-chromium alloys containing similar to 10 at% aluminum and similar to 22 at% chromium, doped with an over-critical concentration of REs, i.e., Zr and Hf. All samples were investigated after thermal exposure at 1100 degrees C by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atom probe tomography (APT). As a result of the overdoping, a considerable increase in oxide growth, an increase in the depth of internal oxidation, and RE-oxide formation near and at oxide grain boundaries (GBs) were observed as a consequence of increased inward and outward diffusion. The effect of overdoping manifests itself differently depending on the RE type and amount due to different solubility, ionic size, and electronic structure of alumina. The sample with Zr retained the adhesion of alumina to the alloy after the first and second thermal exposure, while Hf overdoping resulted in severe spallation after the second thermal exposure.

Keywords

Overdoping; Reactive element; Grain boundary; Alumina

Authors

DARADKEH, S.; MOUSA, M.; SOBOLA, D.

Released

1. 2. 2024

Publisher

SPRINGER

Location

NEW YORK

ISBN

2731-8397

Periodical

HIGH TEMPERATURE CORROSION OF MATERIALS

Year of study

101

Number

1

State

United States of America

Pages from

41

Pages to

59

Pages count

19

URL

BibTex

@article{BUT187836,
  author="DARADKEH, S. and MOUSA, M. and SOBOLA, D.",
  title="Oxidation Behavior and Outward Diffusion of Al Along Oxide Grain Boundaries of FeCrAl Alloys Overdoped with Zr and Hf",
  journal="HIGH TEMPERATURE CORROSION OF MATERIALS
",
  year="2024",
  volume="101",
  number="1",
  pages="41--59",
  doi="10.1007/s11085-023-10204-z",
  issn="2731-8397",
  url="https://link.springer.com/article/10.1007/s11085-023-10204-z"
}