Weaver NDT is a Certified Service Disabled Veteran Owned Small Business

X-Ray Diffraction Explained



  • X-ray diffraction is a non-destructive analytical technique which can yield the unique fingerprint of a crystaline structure.


  • A material's crystal structure is built of layered planes, which act as a mirror. X-rays with a wavelength similar to the distances between these planes can be reflected such that the angle of reflection is equal to the angle of incidence. This behavior is called `diffraction´ and it is described by Bragg's Law: 2dsinθ = nλ


  • Diffracted X-rays will be picked up by the detector scanning at a specific angle. The positions of these reflections will provide the inter-layer spacing's of atoms in the crystal structure.

 

  • Peak intensities provide information about how much X-ray scattering is contributing to that reflection. This information allows for determination of where particular atoms lie in the structure, or how much of a phase is present in a sample.


  • Analysis of the diffraction pattern allows the identification of phases within a given sample. With that achieved, it is possible to quantify each phase present, the crystal structures and their lattice parameters, crystallite size and strain... all information that can be vital in material characterization and quality control.


XRD for Residual Stress

Micro u-X360s

image11

Portable Low X-ray power (30kV, 1.5mA) 

Cycle time is 90 seconds Full 2D sensor  

Measurement Items:

  • Residual Stress 
  • Retained Austenite 
  • FWHM 
  • Fillet Measurement

Software

image12

Debye ring data reveals 

grain orientation, texture, grain size, 

and other metallurgical items. 

 

Quality Control

image13

 X-ray diffraction (XRD) has made 

residual stress characterization 

easy, fast, and dependable.

Residual Stress

Power Generation

image14

Manufacturing process can induce residual stresses that can lead to fatigue cracking and stress corrosion cracking. These conditions can 

premature failures in components.

Automotive

image15

Measurement of residual stresses in automotive components is an essential tool for process consistency and failure analysis. 

Aerospace

image16

Residual stress measurements are 

critical in determining life of aerospace 

structures and components. 

Additive Manufacturing

image17

Powder Bed Fusion 3D Printers can produce repeatable and almost identical parts, 

but the process be building parts with 

inconsistent residual stresses.  



Pipelines and Welds

image18

The dramatic effect that residual stresses 

have on pipelines can help propagate:

  • Hydrogen Induced Cracking
  • Fatigue Cracking
  • and Stress Corrosion Cracking

Shot Peening

image19

Monitors proper and beneficial shotpeening 

for 100% inspection while identifying 

under peening and overpeening. Improper peening can decrease the service life of a component.