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Contour Method: Principle

 
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   - make cut
   - measure surface
   - calculate stress
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   - bent beam
   - weld plate
   - quenched steel
   - impacted plate
   - alum. forging
   - friction stir weld
   - Ti FSW
   - Railroad rails
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Residual Stress
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Measure multiple stress components using one cut, multiple techniques, and superposition

To measure multiple stress components with multiple cuts see:
download preprint Pagliaro, P., Prime, M. B., Swenson, H., and Zuccarello, B., "Measuring Multiple Residual-Stress Components Using the Contour Method and Multiple Cuts," Experimental Mechanics, 50(2), pp. 187-194, 2010. (LA-UR-09-01120)

Basic Contour Method:


 

The Contour Method is Based on an Elastic Superposition Principle:

Initial residuaol stresses
Start with your part. These are the residual stresses that you would like to measure

Experimentally cut the part in two. The part will deform from the release of the stresses

Then experimentally measure the contour, or shape, of the newly created surface


Now analytically force the cut surface back flat. This gives the original residual stresses normal to the cut plane!

It really is simple, but gives you a full 2-D map of the original residual stresses over the cross-section of the part!


Details:

 

 

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Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA
contact: Mike Prime at prime@lanl.gov | Copyright & Disclaimer
U.S. patent 6,470,756 | Last Modified: July 28, 2017

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