Sintering with sps/fast uranium fuel with or without burnable absorbers

Patent metadata

Field	Value
Publication number	US-2020258642-A1
Application number	US-201916273591-A
Country	US
Kind code	A1
Filing date	Feb 12, 2019
Priority date	Feb 12, 2019
Publication date	Aug 13, 2020
Grant date	—

Abstract

The present invention relates to nuclear fuel compositions including uranium dioxide with integral fuel burnable absorber, and triuranium disilicide and a composite of uranium mononitride and triuranium disilicide with or without integral fuel burnable absorber, and methods of sintering these compositions. The sintering is conducted using SPS/FAST apparatus and techniques. The sintering time and temperature is reduced using SPS/FAST as compared to conventional sintering methods for nuclear fuel compositions. The nuclear fuel compositions of the present invention are particularly useful in light water reactors.

First claim

What is claimed is:

1 . A method of sintering a fuel composition, comprising:
forming a powder sample, comprising:
a material selected from the group consisting of triuranium disilicide with or without an integral fuel burnable absorber, a composite of uranium mononitride and triuranium disilicide with or without an integral fuel burnable absorber and
uranium dioxide with an integral fuel burnable absorber;
employing a SPS/FAST system, comprising:
a power supply; and
a vacuum chamber structured to enclose components, comprising:
an upper electrode and a lower electrode;
an upper punch connected to the upper electrode and a lower punch connected to the lower electrode; and
a die assembly constructed of a conductive material, positioned between the upper and lower punches, and structured to hold the powder sample;

introducing the powder sample into the die assembly; passing pulsed direct current from the power supply through the die assembly; heating the powder sample; contacting and compressing the powder sample between the upper punch and the lower punch; and sintering the powder sample.

2 . The method of claim 1 , wherein the composite of uranium mononitride and triuranium disilicide comprises from greater than zero to about fifty percent by weight triuranium disilicide.

3 . The method of claim 1 , wherein the powder sample comprises a mixture of the triuranium disilicide and the integral fuel burnable absorber.

4 . The method of claim 1 , wherein the powder sample comprises a mixture of the composite of uranium mononitride and triuranium disilicide, and the integral fuel burnable absorber.

5 . The method of claim 1 , wherein the powder sample comprises a mixture of the uranium dioxide and the integral fuel burnable absorber.

6 . The method of claim 1 , wherein the integral fuel burnable absorber is selected from the group consisting of UB 2 , UB 4 , ZrB 2 , B, B 4 C, SiBn and mixtures thereof.

7 . The method of claim 1 , wherein the heating of the powder sample is to a temperature in a range from about 1000° C. to about 1700° C.

8 . The method of claim 1 , wherein the sintering of the powder sample is conducted in a time period of about 0.5 minute to about sixty minutes.

9 . The method of claim 7 , wherein the sintering of the powder sample is conducted in a time period of about five minutes to about ten minutes.

10 . The method of claim 1 , wherein the conductive material is selected from the group consisting of graphite, boron nitride, tungsten carbide, molybdenum, tantalum and mixtures thereof.

11 . A method of forming a water corrosion resistant fuel microstructure, comprising:
forming a powder sample, comprising:
a composite of polycrystalline uranium mononitride grain bonded with triuranium disilicide with or without an integral fuel burnable absorber;
employing a SPS/FAST system, comprising:
a power supply; and
a vacuum chamber structured to enclose components, comprising:
an upper electrode and a lower electrode;
an upper punch connected to the upper electrode and a lower punch connected to the lower electrode; and
a die assembly constructed of a conductive material, positioned between the upper and lower punches, and structured to hold the powder sample;

introducing the powder sample into the die assembly; passing pulsed direct current from the power supply through the die assembly; heating the powder sample to a temperature at or above the melting point of triuranium disilicide; contacting and compressing the powder sample between the upper punch and the lower punch; and sintering the powder sample.

12 . The method of claim 10 , wherein the powder sample comprises the composite of polycrystalline uranium mononitride grain bonded with triuranium disilicide and the integral fuel burnable absorber.

13 . The method of claim 11 , wherein the integral fuel burnable absorber is selected from the group consisting of UB 2 , UB 4 , ZrB 2 , BN and mixtures thereof.

14 . The method of claim 12 , wherein a U—Si—B glass phase is formed.

Assignees

• Westinghouse Electric Co Llc

Inventors

• Xu Peng
• Cai Lu
• Ogunji Sylvester F
• Lahoda Edward J
• Hallstadius Lars

Classifications

• G21C7/04

  of burnable poisons (burnable poisons in fuel rods G21C3/326) · CPC title

• G21C3/62

  Ceramic fuel · CPC title

• G21C3/045

  Pellets · CPC title

• C22C29/14 Primary

  based on borides · CPC title

• G21C3/58

  Solid reactor fuel {Pellets made of fissile material} · CPC title