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Title: Forging of FeAl intermetallic compounds

Abstract

Much activity has been concentrated on the development of intermetallic compounds with the aim of improving tensile ductility, fracture toughness and high notch sensitivity in order to develop an attractive combination of properties for high and low temperature applications. This paper reports experience in processing and forging of FeAl intermetallic of B2 type. During the experiments two different temperatures were employed, and the specimens were forged after annealing in air, 10{sup {minus}2} torr vacuum and argon. From the results it was learned that annealing FeAl in argon atmosphere prior to forging resulted in better deformation behavior than for the other two environments. For the higher forging temperature used in the experiments (700C), the as-cast microstructure becomes partially recrystallized.

Authors:
; ; ;  [1];  [2]
  1. UNAM, Cuernavaca (Mexico). Lab. de Cuernavaca
  2. Oak Ridge National Lab., TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab., TN (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States); Consejo Nacional de Ciencia y Tecnologia (CONACYT), Mexico City (Mexico)
OSTI Identifier:
10179461
Report Number(s):
CONF-940286-6
ON: DE94018124; CNN: Grant 2075 - A9203
DOE Contract Number:
AC05-84OR21400
Resource Type:
Conference
Resource Relation:
Conference: Metallurgical Society Annual meeting,San Francisco, CA (United States),27 Feb - 3 Mar 1994; Other Information: PBD: [1994]
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; IRON ALLOYS; FORGING; ALUMINIUM ALLOYS; INTERMETALLIC COMPOUNDS; MICROSTRUCTURE; FRACTOGRAPHY; ANNEALING; 360101; PREPARATION AND FABRICATION

Citation Formats

Flores, O., Juarez, J., Campillo, B., Martinez, L., and Schneibel, J.H.. Forging of FeAl intermetallic compounds. United States: N. p., 1994. Web.
Flores, O., Juarez, J., Campillo, B., Martinez, L., & Schneibel, J.H.. Forging of FeAl intermetallic compounds. United States.
Flores, O., Juarez, J., Campillo, B., Martinez, L., and Schneibel, J.H.. Thu . "Forging of FeAl intermetallic compounds". United States. doi:. https://www.osti.gov/servlets/purl/10179461.
@article{osti_10179461,
title = {Forging of FeAl intermetallic compounds},
author = {Flores, O. and Juarez, J. and Campillo, B. and Martinez, L. and Schneibel, J.H.},
abstractNote = {Much activity has been concentrated on the development of intermetallic compounds with the aim of improving tensile ductility, fracture toughness and high notch sensitivity in order to develop an attractive combination of properties for high and low temperature applications. This paper reports experience in processing and forging of FeAl intermetallic of B2 type. During the experiments two different temperatures were employed, and the specimens were forged after annealing in air, 10{sup {minus}2} torr vacuum and argon. From the results it was learned that annealing FeAl in argon atmosphere prior to forging resulted in better deformation behavior than for the other two environments. For the higher forging temperature used in the experiments (700C), the as-cast microstructure becomes partially recrystallized.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Sep 01 00:00:00 EDT 1994},
month = {Thu Sep 01 00:00:00 EDT 1994}
}

Conference:
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  • Although the B2-type intermetallic compounds, NiAl, FeAl, NiTi and FeTi all maintained a high degree of order during irradiation, metastable phase formation was observed. Dislocation loops and network developed in NiAl and FeAl during irradiation and a nickel rich, fcc phase, most likely disordered Ni/sub 3/Al, formed in NiAl after high doses. The build-up of constitutional vacancies (excess vacancies on Ni sites) and subsequent elemental partitioning of Ni and Al can explain the formation of a nickel rich phase in NiAl. No metastable phases formed in FeAl. Dislocation loop structures did not develop in NiTi or FeTi, rather a transformationmore » to an amorphous phase occurred at relatively low doses. The amorphous transformation results when the free energy of the crystal lattice containing a high defect concentration exceeds the free energy of the amorphous configuration.« less
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