Phased Contrast Analysis

   
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Introduction

  • Earlier detection of material degradation
  • Lifetime health monitoring
  • Failure prediction
  • Component life extension
  • Used for metals and composites
tunable to any depth and any material, without tear down
     
PCA produces a pulsed, tunable monochromatic X-Ray beam. The normal X-Ray you are used to is polychromatic. There is a huge difference.

PCA can be tuned for any material, and to almost any depth so can “see into” machines, such as an aircraft and look at just the nickel-alloy parts for example, even without removing the skin.
all before a fracture occurs
 
The polychromatic X-Ray averages out much of the signal on the K-edge, but PCA sees the real response and can deliver much greater intelligence on what is happening.

To the right is a picture of an advanced aviation composite material that has some fasteners in it. The left picture was taken using current X-Ray technology and the rightmost picture ws taken using PCA.

The PCA picture can see much greater depth, much greater clarity - with visible defects down to 4 nanometers!

Finally, we have a composite test that is better than a person tapping the surface with their hand.
     

Basic Theory

  • polychromatic x-ray theory is well understood in NDE
  • standard tubes put out all 'colors' of x-ray
  • low energy photons contribute to dose
  • high energy photons contribute to scatter
  WhitePaper
Synchrotron Refraction CT
and Synchrotron Bragg Magnification CT for NDE
  • eliminate the highest and lowest energy photons
  • tune x-rays to within the useful ranges
  • use photon and laser beam for x-ray laser solution
  • produce pulsed, tunable, monochromatic x-ray
  • use inverse Compton scattering process
  WhitePaper
Non-Destructive Micro Crack Detection
in Modern Materials
  • each electron is bound in its orbit by a characteristic energy
  • binding energy is different for each atom in the periodic table
  • tune the x-ray to knock the k-shell electron out of orbit
  • produce pulse beam to reduce radiation significantly
  • produce high speed imaging capability
  WhitePaper
X-Ray Refraction Topography and Computed Tomography
for NDE of Lightweight Materials
 
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