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Title: Design, properties, and weldability of advanced oxidation-resistant FeCrAl alloys

Abstract

FeCrAl alloys are promising as corrosion- and oxidation-resistance materials for extreme high-temperature applications. However, further alloy design and improvement requires a delicate balance between workability, weldability, propensity for '-phase formation, among other factors. Here, a series of advanced oxidant resistant FeCrAl alloys were produced and investigated. Variants with Al (+2%), Nb (+1%), and TiC (0.1, 0.3, and 1%) additions over the reference alloy (Fe-13%Cr-5%Al) were characterized in detail before and after controlled laser beam welding using tensile tests with digital image correlation, SEM-EBSD analysis, and fractography. All investigated alloys demonstrated yield stress in the weldment over 500 MPa; no welding-induced cracking was observed. However, it was shown that the increase in the Al-content over 5% was detrimental leading to a brittle fracture mechanism and decreased ductility in the weldment. At the same time, Nb and TiC additions were beneficial for preventing grain growth and reducing local softening (yield stress reduction) in the heat-affected zone. The 1% TiC addition also effectively refined grain size in the weldment.

Authors:
 [1];  [1];  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
Sponsoring Org.:
USDOE
OSTI Identifier:
1361343
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Materials & Design
Additional Journal Information:
Journal Volume: 129; Journal Issue: C; Journal ID: ISSN 0264-1275
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Gussev, M. N., Field, K. G., and Yamamoto, Y. Design, properties, and weldability of advanced oxidation-resistant FeCrAl alloys. United States: N. p., 2017. Web. doi:10.1016/j.matdes.2017.05.009.
Gussev, M. N., Field, K. G., & Yamamoto, Y. Design, properties, and weldability of advanced oxidation-resistant FeCrAl alloys. United States. doi:10.1016/j.matdes.2017.05.009.
Gussev, M. N., Field, K. G., and Yamamoto, Y. Fri . "Design, properties, and weldability of advanced oxidation-resistant FeCrAl alloys". United States. doi:10.1016/j.matdes.2017.05.009. https://www.osti.gov/servlets/purl/1361343.
@article{osti_1361343,
title = {Design, properties, and weldability of advanced oxidation-resistant FeCrAl alloys},
author = {Gussev, M. N. and Field, K. G. and Yamamoto, Y.},
abstractNote = {FeCrAl alloys are promising as corrosion- and oxidation-resistance materials for extreme high-temperature applications. However, further alloy design and improvement requires a delicate balance between workability, weldability, propensity for '-phase formation, among other factors. Here, a series of advanced oxidant resistant FeCrAl alloys were produced and investigated. Variants with Al (+2%), Nb (+1%), and TiC (0.1, 0.3, and 1%) additions over the reference alloy (Fe-13%Cr-5%Al) were characterized in detail before and after controlled laser beam welding using tensile tests with digital image correlation, SEM-EBSD analysis, and fractography. All investigated alloys demonstrated yield stress in the weldment over 500 MPa; no welding-induced cracking was observed. However, it was shown that the increase in the Al-content over 5% was detrimental leading to a brittle fracture mechanism and decreased ductility in the weldment. At the same time, Nb and TiC additions were beneficial for preventing grain growth and reducing local softening (yield stress reduction) in the heat-affected zone. The 1% TiC addition also effectively refined grain size in the weldment.},
doi = {10.1016/j.matdes.2017.05.009},
journal = {Materials & Design},
number = C,
volume = 129,
place = {United States},
year = {Fri May 05 00:00:00 EDT 2017},
month = {Fri May 05 00:00:00 EDT 2017}
}

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