Neep 541 material properties
This presentation is the property of its rightful owner.
Sponsored Links
1 / 31

NEEP 541 – Material Properties PowerPoint PPT Presentation


  • 48 Views
  • Uploaded on
  • Presentation posted in: General

NEEP 541 – Material Properties. Fall 2003 Jake Blanchard. Outline. Materials in Reactors Fission Fusion Material Properties Tensile tests Impact tests Creep tests. Materials in Reactors. Fission Fuel Cladding Moderator Core structure Reflector Control rods Coolant

Download Presentation

NEEP 541 – Material Properties

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Neep 541 material properties

NEEP 541 – Material Properties

Fall 2003

Jake Blanchard


Outline

Outline

  • Materials in Reactors

    • Fission

    • Fusion

  • Material Properties

    • Tensile tests

    • Impact tests

    • Creep tests


Materials in reactors

Materials in Reactors

  • Fission

    • Fuel

    • Cladding

    • Moderator

    • Core structure

    • Reflector

    • Control rods

    • Coolant

    • Pressure vessel

    • shielding

  • Fusion

    • Fuel

    • Structure

    • Tritium breeder

    • Coolant

    • insulators

    • shielding


Fission

Fission

  • Primary radiation damage is in fuel and cladding

  • Cladding:

    • Adequate strength (T, fluence)

    • Corrosion resistance

    • Thermal conductivity

    • Neutronics (low absorption)

    • Available resources

    • Fabricability

    • Inexpensive


Cladding materials

Cladding Materials

  • Low thermal absorption cross section

    • Al

    • Mg

    • Zr

    • Be

  • High thermal absorption cross section

    • Nb

    • Mo

    • Ta

    • V

    • Ti

    • Steel


Some numbers

Some Numbers


Fusion structure requirements

Fusion Structure Requirements

  • Same as fission plus…

    • Low swelling

    • Low embrittlement

  • Typical Materials

    • Austenitic steel (316 SS)

    • Ferritic steel (lately ODS FS)

    • Refractory alloys

    • composites


Radiation effects

Radiation Effects

  • Radiation hardening (increase in strength)

  • Embrittlement (decrease in ductility)

  • Swelling (volume increase due to voids)

  • Irradiation creep


Tests

Tests

  • Tensile tests (modulus, ductility, strength)

  • Tube burst tests (creep)

  • Impact tests (ductility, fracture toughness)


Tensile tests

Tensile Tests


Understanding the tensile test

Understanding the Tensile Test

  • A0=cross sectional area before test (in test section)

  • A=cross sectional area during test (load=P)

  • L0=section length before test

  • L=section length during test


Tensile tests1

Tensile Tests

  • Engineering stress=eng=P/A0

  • True Stress=true=P/A

  • Before necking, A~A0

  • Engineering strain==(L-L0)/L0

  • True strain=


Stress strain curve

Stress-Strain Curve


True stress true strain

True Stress – True Strain


Combined

Combined


When does necking start

When does necking start?

  • Plastic Instability (dP=0)

Volume is conserved


Plastic instability

Plastic Instability

Necking occurs when slope of true stress-true strain curve=true stress


Plastic instability1

Plastic Instability

  • suppose


Hardening

Hardening


Impact testing

Impact Testing

  • Test for ductility

  • Measure energy absorbed during fracture


Typical results

Typical Results

  • DBTT=ductile to brittle transition temperature

Upper shelf

Lower shelf

E (J)

irradiated

40

T

DBTT


Creep tests

Creep Tests

  • Apply load and measure deformation as a function of time

primary

secondary

tertiary

Creep strain

time


Study creep rupture with a tube burst test

Study creep rupture with a tube burst test

2R

L

p


Burst test analysis

Burst Test Analysis

Slice cylinder vertically

p


Burst test analysis1

Burst Test Analysis

Slice cylinder horizontally (picture is shown cut away vertically as well)


Burst test analysis2

Burst Test Analysis

  • Uniaxial (1-D tensile test)

  • Constant stress


Burst test analysis3

Burst Test Analysis


Burst test analysis4

Burst Test Analysis


Burst test analysis5

Burst Test Analysis


Burst test analysis6

Burst Test Analysis


Burst test analysis7

Burst Test Analysis

  • Negative radial strain means that wall gets thinner

  • Zero axial strain means length doesn’t change

  • Positive hoop strain means radius increases

  • Analysis assumes small strain, constant stress

  • For large strain, wall thins and stress increases, leading to rupture


  • Login