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Fracture Toughness Testing Enquiry Form

Welcome to our new Fracture Toughness Testing enquiry form. We hope you will find it useful when specifying your testing requirements.

You will be able to upload any additional documents and images after completing the form.

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Tensile Properties (Notch Position Parent)

Tensile Properties (Notch Position Weld)

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A notification email has been sent to your email address. If you have additonal information or client specific specifications (documents, images etc.) please reply to the email and send them as attachments. If the documents are over 10mb in size please contact us to arrange a large file transfer

The formula for calculating depth ratio is a~0~/W, where a~0~ is the initial crack length and W is the specimen width.

0.5 is standard for single point tests, 0.55 for unloading compliance tests and for all specimen types except CCT where a/W is a range 0.25-0.4

If the test is an unloading compliance test it is usual to use sidegrooves.

If the material available is large enough to accommodate the cross-section required for testing, but not the complete length of the specimen, then extensions may be welded on using electron beam welding.

The extension material should be either of the following:

  • Nominally the same material – this could come from a different part of the source material or a different orientation to that required for testing.
  • A similar material – this should have similar yield and ultimate tensile strengths to the test material and be of a similar type (eg if you have a stainless steel specimen, best to do the extensions out of a stainless too).

Please indicate the number of specimens to be tested

Recommended for material in the as-welded condition to relieve residual stresses prior to fatigue pre-cracking. Not required if Notch Position is Parent

e.g. mill certificate, testing at ambient, testing at test temperature, assumed from data

e.g. mill certificate, testing at ambient, testing at test temperature, assumed from data

e.g. pre-straining, heat treatment, soaking in environment

Apart from that required by the testing standard e.g. for HAZ notched specimens targeting a specific microstructure (SM)

For example:

  • Confirming a notch position in relation to a fusion line (the outcome is a value in mm)
  • Quantifying the proportion of a certain microstrcucture (the outcome is a % CGHAZ)
  • A qualitative description of the microstructure at the notch tip (the outcome would be 'ICGCHAZ')
  • A pop-in assessment (where the outcome would be critical pop-in yes/no)

Please select a standard. The requirement for Sidegrooves changes depending on the standard selected.