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Title: Influence of Particle Dispersions on the High-Temperature Strength of Ferritic Alloys

Abstract

Four ferritic alloys based on the composition Fe-14Cr-3W-0.4Ti (nominal wt.%) were developed with a predominant dispersion of either oxide particles or nano-size Y-,Ti-,O-rich clusters, or nanoclusters (NC). Tensile specimens machined from the alloys were tested at room temperature and at temperatures ranging from ~360 C to 800 C in air using a strain rate of 10 3s 1. The results showed that the high-temperature strength of the NC strengthened alloys was significantly better than that of the oxide strengthened alloys. The room temperature yield strengths of the two alloys containing the NC were 1469MPa and 1261MPa while the yield strengths of the two oxide dispersion alloys were 819MPa (Y-Ti-oxides) and 583MPa (Ti-oxides). However, the ductility of the oxide strengthened alloys was better than that of the NC strengthened alloys.

Authors:
 [1];  [1];  [1];  [1];  [2];  [3]
  1. ORNL
  2. University of California, Santa Barbara
  3. University of California, Berkeley
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shared Research Equipment Collaborative Research Center
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program; Work for Others (WFO)
OSTI Identifier:
931625
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: ICFRM-12, Santa Barbara, CA, USA, 20051204, 20051209
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AIR; ALLOYS; DUCTILITY; OXIDES; STRAIN RATE; YIELD STRENGTH

Citation Formats

Hoelzer, David T, Bentley, James, Sokolov, Mikhail A, Miller, Michael K, Odette, George R., and Alinger, M. J. Influence of Particle Dispersions on the High-Temperature Strength of Ferritic Alloys. United States: N. p., 2007. Web.
Hoelzer, David T, Bentley, James, Sokolov, Mikhail A, Miller, Michael K, Odette, George R., & Alinger, M. J. Influence of Particle Dispersions on the High-Temperature Strength of Ferritic Alloys. United States.
Hoelzer, David T, Bentley, James, Sokolov, Mikhail A, Miller, Michael K, Odette, George R., and Alinger, M. J. Mon . "Influence of Particle Dispersions on the High-Temperature Strength of Ferritic Alloys". United States. doi:.
@article{osti_931625,
title = {Influence of Particle Dispersions on the High-Temperature Strength of Ferritic Alloys},
author = {Hoelzer, David T and Bentley, James and Sokolov, Mikhail A and Miller, Michael K and Odette, George R. and Alinger, M. J.},
abstractNote = {Four ferritic alloys based on the composition Fe-14Cr-3W-0.4Ti (nominal wt.%) were developed with a predominant dispersion of either oxide particles or nano-size Y-,Ti-,O-rich clusters, or nanoclusters (NC). Tensile specimens machined from the alloys were tested at room temperature and at temperatures ranging from ~360 C to 800 C in air using a strain rate of 10 3s 1. The results showed that the high-temperature strength of the NC strengthened alloys was significantly better than that of the oxide strengthened alloys. The room temperature yield strengths of the two alloys containing the NC were 1469MPa and 1261MPa while the yield strengths of the two oxide dispersion alloys were 819MPa (Y-Ti-oxides) and 583MPa (Ti-oxides). However, the ductility of the oxide strengthened alloys was better than that of the NC strengthened alloys.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
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