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Nuclear Reactor – Current state, challenges and future needs from materials perspective

Nov 21, 2019

Kurt TerraniTCR Technical Director

22

Outline

• Current status

• Towards high dose

• Towards high temperature

• What is TCR?

• Opportunities in advanced manufacturing

– Advanced processing and designs

– new approach to qualification

Zinkle, Snead, Annu. Rev. Mater. Res. 2014. 44:241–67

33

40

50

60

70

80

90

100

1970 1980 1990 2000 2010

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 2020

304SS

IN 600

316SSA286

17-4 PHA302B

X750 Zr-2IN 800

Zr-4

IN 690

A533B Zirlo & M5

US Electricity >10% Nuclear

US Nuclear Capacity FactorHits 90%

RPV Embrittlement Concerns Confirmed

Fuel Failure Rate ~1ppm

Fuel Failure Rate = 0

Zero Failure By 10 Initiative

FukushimaChernobyl

TMI-2

Core StructureHigh StrengthSteam GeneratorRPVCladding

A Timeline

No new materials after

1970s

44

It has been 40 years since a non-LWR reactor was started up in the United States

• New nuclear energy is associated with high costs and long timelines with large uncertainty

• Few if any technological advances in design, materials, sensing, and qualificationapproach have been brought to bear since the 1970s

FFTF core, HEDL

55

Towards high dose

66

Basic Definitions

• Structural materials are those that are primarily responsible to bear a load and maintain geometry with specific strength or strain requirements

• Radiation stability for nuclear structural applications is defined as the ability of the material to limit its dimensional change to an acceptable design envelope and to withstand degradation in mechanical properties as a function of irradiation dose

time + stress + temperature + radiation

77

Realization of radiation tolerant materials relies on three distinct strategies• Immobile point defects

• Crystal structure with intrinsic resistance (BCC)

• High density of recombination centers (surfaces)

1%/dpa

30 nm

Zinkle, Snead, Annu. Rev. Mater. Res. 44 (2014) 241–67

S.J. Zinkle & G.S. Was, ActaMater. 61(2013) 735

C. Massey et al., Acta Mater. 166 (2019)

FeCrAl ODS

88

Towards high temperature

99

High temperature operation requires microstructural stability and creep resistance • Fine precipitates in metal alloys

• Refractory metals

• Ceramics (CMCs)

D. Hoelzer et al., J. Nucl. Mater. (2020)

-12

-10

-8

-6

-4

-2

0

1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3

550ºC - OFRAC

600ºC - OFRAC

700ºC - OFRAC

800ºC - OFRAC

650ºC - 316 SS

650ºC - 316LN SS

650C - X6CrNiTi18-10 SS

Lo

g [

(s-1

)]

. min

Log [ (MPa)]

550ºC

600ºC700ºC800ºC

650ºC

650ºC

CVD-SiC RB-SiC

1010

What is TCR?

1111

Reliable,

available, and

low-cost clean

energy

facilitated using

modern

technology

Rapidly

demonstrate

application of

advanced

manufacturing

to build and

deploy an

efficient nuclear

energy system

VisionMission

Transformational Challenge Reactor is committed to an

audacious timeline to build and operate a 3D-printed

reactor core

Enable adoption of technologies by U.S. nuclear

industry and regulator

Phase IIIPhase IIPhase IFeb

2019

Feb

2021

Feb

2023

Jan

2025

Nuclear Demo

1212

Opportunities in advanced manufacturing- Advanced processing and designs

1313

How is the design approach different with TCR?

Identify issues

Measure properties

model

Identify l imitations

Manufacture core structure

Manufacture fuel

Manufacture moderator

consolidate

Using CAD software with topology

optimization to arrive at complex geometries

• fundamental design and manufacturing principles

• Physical, component, regulatory constrains

1414

3D printing of nuclear-grade SiC in complex geometries

Binder jet printing

chemical vapor infiltrationCAD model

1cm

1515

Design optimization via parallel modeling, manufacturing, and testing

Temperature [°C]0 200 400 600 800 1000

Th

erm

al con

du

ctivity [

W/m

-K]

0

5

10

15

20

25

30

35

40

unirradiated

0.001 dpa

0.01 dpa

0.1 dpa

10 dpa

1 dpa

increasing dose

K. Terrani, B. Jolly, M. Trammell, “3D printing of high-purity silicon carbide” J. Am. Cer. Soc., (2019) DOI: 10.1111/jace.16888

1616

Opportunities in advanced manufacturing- New approach to qualification

1717

Is it possible to exploit Advanced Manufacturing to deliver a new approach to qualification?

Conform to feedstock

quality requirements

Conform to manufacturing

quality requirements

Conform to examination

quality requirements

pass pass

pass

Qualified component

Rejected

failure

Conventional Qualification Scheme

Collect feedstock

data

Collect spatially selective data

throughout manufacturing

Data repository Qualified component

Rejected component

Trained data analytics

Collect environmental

data during manufacturing

provide live feedback to manufacturing

Instantaneously ascertain quality

New Qualification Scheme

1818

Fins to hold fuel and conduct heat

Lid to be welded on top

Cooling channels

TCR fuel cladding concept

Monitoring to assess quality during advanced manufacturing (in situ)

1919

Establishing links between in situ and ex situ data

25 mm

50 mm

75 mm

100 mm

125 mm

150 mm

175 mm

Err

or d

ete

cti

on

ra

te (

un

itle

ss)

y100 110 120 130 140

800

850

900

950

1000

Tem

per

atu

re (°C

)Hoop Stress (MPa)

Laser 1

Laser 2

Line Defect

No Defect

y

1 5 50 500

600

800

1000

1200

1400

Tem

per

atu

re (°C

)

Hoop Stress (MPa)

Laser 1Laser 2Line DefectNo Defect

20% CW 316 - SSA 316 - S20% CW 316 - C20% CW 316 - GCFR

5-5.6°C/s

2020

A new approach to qualification is warranted and possible

Collect

feedstock

data

Collect spatially

selective data

throughout

manufacturing

Data repository

Train data analytics framework

Collect

environmental

data during

manufacturing

Collect

performance

data

Manufacturing data (input)testing data

(output)

2121

Summary

• Nuclear energy advancement requires new materials, manufacturing methods, and approaches to qualification

• Advanced nuclear energy systems require materials that can withstand higher dose and temperature regimes. Strategies for radiation tolerance and classes of materials that offer high temperature operation capability are known.

• Advanced manufacturing when performed in parallel with design and testing allows for an agile and informed development process

• In situ data during additive manufacturing have the potential to provide a new paradigm for critical component qualification