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Title: EFFECTS OF OXIDE PRECURSOR PREPARATION PARAMETERS ON THE ELECTROCHEMICAL REDUCTION OF TANTALUM PENTOXIDE IN CALCIUM CHLORIDE MELT

Abstract

The contents of the paper shall be presented as an oral presentation. The contents will be subsequently published as a reviewed paper in the conference proceeding.

Authors:
; ; ;
Publication Date:
Research Org.:
Idaho National Lab. (INL), Idaho Falls, ID (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1372787
Report Number(s):
INL/CON-16-39916
Journal ID: ISSN 2367--1181
DOE Contract Number:
DE-AC07-05ID14517
Resource Type:
Conference
Resource Relation:
Conference: 146th Annual Meeting & Exhibition, TMS, San Diego, USA, February 26–March 3, 2017
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Electrochemical Reduction; Residual Oxygen; Sintered Tantalum Pentoxide

Citation Formats

Chorney, Maureen P., Hurley, Bridger P., Tripathy, Prabhat, and Downey, Jerome P.. EFFECTS OF OXIDE PRECURSOR PREPARATION PARAMETERS ON THE ELECTROCHEMICAL REDUCTION OF TANTALUM PENTOXIDE IN CALCIUM CHLORIDE MELT. United States: N. p., 2016. Web. doi:10.1007/978-3-319-51493-2_62.
Chorney, Maureen P., Hurley, Bridger P., Tripathy, Prabhat, & Downey, Jerome P.. EFFECTS OF OXIDE PRECURSOR PREPARATION PARAMETERS ON THE ELECTROCHEMICAL REDUCTION OF TANTALUM PENTOXIDE IN CALCIUM CHLORIDE MELT. United States. doi:10.1007/978-3-319-51493-2_62.
Chorney, Maureen P., Hurley, Bridger P., Tripathy, Prabhat, and Downey, Jerome P.. 2016. "EFFECTS OF OXIDE PRECURSOR PREPARATION PARAMETERS ON THE ELECTROCHEMICAL REDUCTION OF TANTALUM PENTOXIDE IN CALCIUM CHLORIDE MELT". United States. doi:10.1007/978-3-319-51493-2_62.
@article{osti_1372787,
title = {EFFECTS OF OXIDE PRECURSOR PREPARATION PARAMETERS ON THE ELECTROCHEMICAL REDUCTION OF TANTALUM PENTOXIDE IN CALCIUM CHLORIDE MELT},
author = {Chorney, Maureen P. and Hurley, Bridger P. and Tripathy, Prabhat and Downey, Jerome P.},
abstractNote = {The contents of the paper shall be presented as an oral presentation. The contents will be subsequently published as a reviewed paper in the conference proceeding.},
doi = {10.1007/978-3-319-51493-2_62},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 9
}

Conference:
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  • In recent years, TiAl-based intermetallic alloys are being increasingly considered for application in areas such as (i) automobile/transport sector (passenger cars, trucks and ships) (ii) aerospace industry (jet engines and High Speed Civil Transport propulsion system) and (iii) industrial gas turbines. These materials offer excellent (i) high temperature properties (at higher than 6000C) (ii) mechanical strength and (iii) resistance to corrosion and as a result have raised renewed interest. The combination of these properties make them possible replacement materials for traditional nickel-based super-alloys, which are nearly as twice as dense (than TiAl based alloys). Since the microstructures of these intermetallicmore » alloys affect, to a significant extent, their ultimate performance, further improvements (by way of alteration/modification of these microstructures), have been the subject matter of intense research investigations. It has now been established that the presence of alloy additives, such as niobium, tantalum, manganese, boron, chromium, silicon, nickel and yttrium etc, in specific quantities, impart marked improvement to the properties, viz. fatigue strength, fracture toughness, oxidation resistance and room temperature ductility, of these alloys. From a number of possible alloy compositions, {gamma}-TiAl and Ti-Al-Nb-Cr have, of late, emerged as two promising engineering alloys/materials. . The conventional fabrication process of these alloys include steps such as melting, forging and heat treatment/annealing of the alloy compositions. However, an electrochemical process offers an attractive proposition to prepare these alloys, directly from the mixture of the respective oxides, in just one step. The experimental approach, in this new process, was, therefore, to try to electrochemically reduce the (mixed) oxide pellet to an alloy phase. The removal of oxygen, from the (mixed) oxide pellet, was effected by polarizing the oxide pellet against a graphite electrode in a pool of molten calcium chloride at a temperature of 9000C. The dominant mechanism of the oxygen removal was the ionization of oxygen followed by its subsequent discharge, as CO2/CO, at the anode surface. The removal of oxygen from the oxide mixture helped form the alloy in situ. The presentation shall cover the detailed experimental results pertaining to the preparation, evaluation and characterization of Ti-47Al-2Nb-2Cr (atom%) alloy.« less
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