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Densification of thoria through flash sintering

Published online by Cambridge University Press:  11 September 2017

W. Straka ,
S. Amoah  and
J. Schwartz
W. Straka*
Affiliation:
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27606, USA
S. Amoah
Affiliation:
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27606, USA Department of Physics, Lenoir Rhyne University, Hickory, NC 28601, USA
J. Schwartz
Affiliation:
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27606, USA
*
Address all correspondence to W. Straka at [email protected]
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Abstract

Thorium dioxide (thoria, ThO2) is used in refractory applications and as nuclear fuel. Its melting temperature, the highest of any binary oxide, makes it a difficult system to process. Here we report on the effects of flash sintering on the densification of thoria. We found 95% of theoretical density is obtained at ~950 °C (~30% of the melting temperature) with an electric field of 800 V/cm. Variation in power density had a minimal effect on the densification. Scanning electron microscopy images show the effects of flash sintering on grain size as a function of electric field.

Type
Research Letters
Information
MRS Communications , Volume 7 , Issue 3 , September 2017 , pp. 677 - 682
Copyright
Copyright © Materials Research Society 2017 

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