Multilayer Fuel Cladding with Ceramic Composite Core

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional fuel rod claddings face challenges in maintaining hermeticity, mechanical strength, and corrosion resistance at high temperatures, particularly in ceramic materials which are prone to embrittlement and swelling, and there is a need for a material that can provide all these properties simultaneously.

Innovation Solution

A multilayer cladding system comprising an inner metallic layer, an intermediate ceramic composite layer with interlocking woven or braided fibers, and an outer metallic layer, which provides hermeticity, mechanical support, and corrosion resistance, while allowing for deformation without cracking and reforming a protective oxide layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If ceramic materials are used for high temperature strength, then temperature resistance is improved, but mechanical toughness and hermeticity deteriorate due to embrittlement and swelling

Engineering Contradiction:
Improvehigh temperature strengthVSAvoidhermeticity
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent employs a composite cladding structure consisting of an inner metallic layer (providing hermeticity and ductility) and an outer ceramic layer (providing high temperature strength and corrosion resistance). This composite approach allows the cladding to simultaneously achieve hermeticity from the metallic layer and high temperature resistance from the ceramic layer, resolving the contradiction between these two properties.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The invention uses a nested layer structure where the metallic layer is positioned inside the ceramic layer. The inner metallic layer maintains hermeticity and accommodates deformation, while the outer ceramic layer provides high temperature strength. This nested arrangement allows each material to perform its optimal function without compromising the other.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Stability of the object's composition

If ceramic materials are used for high temperature stability, then temperature stability is improved, but mechanical toughness deteriorates due to embrittlement

Engineering Contradiction:
Improvehigh temperature stabilityVSAvoidmechanical toughness
Core Design Contradiction:
Stability of the object's compositionVSStrength

Solution Approach 1:

The composite cladding combines ceramic material in the outer layer for high temperature stability with metallic material in the inner layer for mechanical toughness. The ceramic layer maintains compositional stability at high temperatures while the metallic layer provides the necessary mechanical toughness and ductility, resolving the contradiction between these properties.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The invention applies different material properties to different layers: the outer ceramic layer is optimized for high temperature stability and corrosion resistance, while the inner metallic layer is optimized for mechanical toughness and hermeticity. This local differentiation of material qualities allows each layer to excel at its specific function.

Inventive Principle:
Principle #3Local quality

3Device complexity

If single material cladding is used, then device complexity is reduced, but ability to provide all desirable properties simultaneously deteriorates

Engineering Contradiction:
Improvecladding structure simplicityVSAvoidmulti-property performance
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent uses a composite cladding structure with multiple layers, each made from different materials optimized for specific functions. The inner metallic layer provides hermeticity and mechanical toughness, while the outer ceramic layer provides high temperature stability and corrosion resistance. This composite approach enables the cladding to simultaneously deliver multiple desirable properties that cannot be achieved with a single material.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The composite cladding structure serves multiple functions through its layered design: the metallic layer provides hermetic sealing and ductility, while the ceramic layer provides high temperature resistance and corrosion protection. This multi-functional design allows a single cladding system to perform all necessary functions simultaneously.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The multilayer cladding system effectively maintains hermeticity, provides high temperature strength and toughness, and offers accident tolerance by combining the benefits of both metallic and ceramic materials, ensuring the containment of fuel and fission products while resisting corrosion and swelling.

Implementation Method 1

an intermediate ceramic composite layer with interlocking woven or braided fibers

Methodology Applied
Scientific EffectFiber reinforcement:

Implementation Method 2

reforming a protective oxide layer

Methodology Applied
Scientific EffectOxidation: Oxidation

Implementation Method 3

provides high temperature strength and toughness, and offers accident tolerance by combining the benefits of both metallic and ceramic materials, ensuring the containment of fuel and fission products while resisting corrosion and swelling

Methodology Applied
Scientific EffectIrradiation resistance:

Data Source

PatentEP3383644B1Multilayer composite fuel clad system with high temperature hermeticity and accident tolerance
Publication Date: 2023.07.19 WESTINGHOUSE ELECTRIC CORP
  • EP3383644B1 patent drawingFigure 1
  • EP3383644B1 patent drawingFigure 2

AI summary

The invention relates to a multilayer cladding including a combination of ceramic and metallic components. The multilayer coating includes an inner layer, an intermediate layer and an outer layer. The inner layer can form the cladding structure, the intermediate layer can include a ceramic composite or ceramic-containing composite composed of interlocking woven or braided fibers, e.g., fiber tows wrapped on the inner layer to form a woven structure, and a matrix material, and the outer can be composed of metal or metal alloy, such as, in the form of a coating. The multilayer cladding is effective to protect contents of the cladding structure from exposure to high temperature environments.