X-Ray Tomography
X-ray micro-tomography is a non-destructive technique used to visualise and characterise objects in three dimensions. The power of the technique lies in the ability to not only to visualise the internal structure of an object but to measure its geometry quantitatively.
The technique works by acquiring a series of x-ray projection images at a known number of angular positions through 360 degrees. Variation in the contrast of each projection image relates to how the x-rays are attenuated as they penetrate the sample. X-ray attenuation increases proportionally to sample material electron density and thickness resulting in a darker projection image. Specialised mathematical calculations known as ‘reconstruction algorithms’ are used to create the 3D image from the x-ray projections. Visualisation software then permits numerous analysis options from creating sections through the 3D image to quantification of size, internal porosity, surface area or segmentation based on difference in density.
The benefits of the technique include:
- Non-destructive high resolution 3-dimensional imaging of the interior of objects
- Non-destructive slice and sectional views in any direction
- Measurements in three dimensions (wall thickness, diameter, surface extraction, etc)
- Quantitative analysis (voids, channels, cracks, particles etc) in three dimensions
- 3D animation as a visualisation tool.
Our Equipment:
SEAM’s dedicated X-ray tomography laboratory has a Phoenix Nanotom™ system (GE Sensing and Inspecting Technologies) contained within a customised air-conditioned safety cabinet. The Nanotom has a 180 kV x-ray gun with a tungsten transmission target and a 2 megapixel high contrast flat panel digital detector.
Analysis of reconstructed 3D data sets is carried out using Volume Graphics VGStudioMax Software. SEAM’s experienced staff are trained in a range of analysis procedures suited to your needs (e.g. geometrical characterisation, surface extraction, defect analysis and production of animated movies of your data).
X-Ray Tomography Examples
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