A review of ceramic coatings for high temperature uranium melting applications

doi:10.1016/j.jnucmat.2020.152354

Journal of Nuclear Materials

Volume 540, November 2020, 152354

https://doi.org/10.1016/j.jnucmat.2020.152354 Get rights and content

Highlights

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Structural materials for Pyrochemical reprocessing applications plays a crucial role.
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Graphite crucibles with Yttria coating is preferred for uranium melting application.
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SiC interlayer coating between graphite and Yttria provides better durability.

Abstract

Pyrochemical reprocessing is being explored for reprocessing of spent metallic fuels of future fast breeder reactors. This process consists of several operations like electrorefining, cathode processing, and fuel casting process. The cathode processing and fuel pin casting processes are carried out at 1073–1723 K. Hence, the process vessels should withstand high temperatures, molten metals, and molten salts. Several structural materials and coatings have been proposed and evaluated for such applications. However, high density graphite (HDG) is the proposed material for process crucibles due to its high temperature compatibility. Bare HDG cannot be used directly due to reactivity with molten uranium and its alloys. Hence, coatings like yttria over HDG are being proposed to avoid undesirable carbon contamination of uranium. This review provides the various coatings and their performance evaluation for molten metal applications, including our recent works on the development of thermal spray coatings for such an application.

Graphical abstract

Graphite crucible with SiC interlayer and APS coated Y2O3 is suitable for U melting experiments

Section snippets

Pyrochemical reprocessing and the need for the development of high temperature coatings

Nuclear power production in India is expected to progress at a faster rate to meet the required and rising power demand. India had a well-charted three stage nuclear power programme initiated by Dr. Homi J. Bhabha, which judiciously uses the available nuclear fuel resources of the nation. Reprocessing of the used nuclear fuel (spent nuclear fuel) is one of the essential steps in sustaining the growth of nuclear power production in India [1]. The oxide-based nuclear fuels are being reprocessed

Development of ceramic coatings for uranium melting applications

The development of structural materials and coatings for handling molten uranium (U) and other metals in the pyrochemical reprocessing has been initiated in the past few decades. A brief review of the works and findings from the literature are provided in Table 1. Feder et al. [9] studied corrosion of ceramic oxides like alumina, magnesia, zirconia, beryllia, and thoria by molten U and its alloys in the temperature range of 1413–1603 K. They found that complex kinetics are involved including

Concluding remarks

Pyrochemical reprocessing and its technologies for metallic fuels reprocessing are currently under research and development worldwide. The structural materials and selection of coatings for the applications in various key unit operations of the pyrochemical reprocessing of the spent metallic fuels for future liquid metal cooled Fast Breeder reactors plays a crucial role in the success of the process. Different types of substrate materials and coatings have been investigated for the

CRediT authorship contribution statement

Jagadeeswara Rao Ch: Conceptualization, Formal analysis, Writing - original draft. E. Vetrivendan: Conceptualization, Formal analysis, Writing - review & editing. B. Madhura: Conceptualization, Formal analysis, Writing - review & editing, Data curation. S. Ningshen: Writing - review & editing, Supervision.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

The authors sincerely thank Director, IGCAR, Director, MMG, AD, MCG and Head, CSTD for their constant support. The authors also acknowledge all the previous and present colleagues of CSTD, MMG, IGCAR. They initiate and helped in the successful execution and also in the continuation of the present research work on materials and coatings programme related to the pyrochemical reprocessing. Authors also thank Shri. P. Venkatesh, Mr S. Mariyappan and Mr A. S. Ganapathi from MC&MFCG, IGCAR for their

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View full text

A review of ceramic coatings for high temperature uranium melting applications

Highlights

Abstract

Graphical abstract

Section snippets

Pyrochemical reprocessing and the need for the development of high temperature coatings

Development of ceramic coatings for uranium melting applications

Concluding remarks

CRediT authorship contribution statement

Declaration of competing interest

Acknowledgements

Prog. Nucl. Energy

Ceram. Int.

Thin Solid Films

Mater. Chem. Phys.

J. Nucl. Mater.

Thin Solid Films

Nucl. Eng. Tech.

J. Eur. Ceram. Soc.

Sur. Coat. Technol.

Thin Solid Films

Ceram. Int.

J. Nucl. Mater.

Ceram. Int.

Indian nuclear power programme – past, present and future

Sadhana

An introduction to the PUREX process

IANCAS Bullet.

Current status of pyrochemical reprocessing research in India

Nucl. Technol.

Development of pyroprocessing technology

Prog. Nucl. Energy

Development of pyrochemical reprocessing for spent metal fuels

Energy Procedia

Status of pyroprocessing technology development in Korea

Nucl. Eng. Technol.

Interaction of Uranium and its Alloys with Ceramic Oxides, Report ANL-5765