additive.tools
Post-Processing/Industrial CT Scanning
inspectioninspection metrology

Industrial CT Scanning

Also known as: X-ray CT, Computed Tomography, Industrial CT, Porosity Analysis, Internal Inspection

Industrial computed tomography rotates a part in an X-ray beam and reconstructs a full 3D voxel volume of its interior. It is the only non-destructive method that reveals internal porosity, lack-of-fusion defects, cracks, inclusions, and the geometry of internal channels — none of which are visible from the outside. Analysis software (Volume Graphics VGSTUDIO, others) quantifies pore size/distribution, measures internal dimensions, and compares the scanned geometry to the nominal CAD (nominal/actual deviation).

Why AM parts need this

AM is uniquely prone to internal defects — gas porosity, lack-of-fusion voids, keyhole pores, and trapped powder in internal channels — that conventional surface inspection cannot detect. For aerospace, medical, and fatigue-critical AM parts, CT is the accepted method to qualify internal integrity and verify that internal channels are clear of powder after depowdering. CT also verifies that conformal cooling channels and lattices match the design intent. Porosity quantified by CT feeds directly into fatigue-life and HIP decisions: high internal porosity flags a part for HIP or rejection.

Key parameters

Voxel (resolution)5–150 µm

Finer voxel = smaller detectable defect, but smaller scannable part. Sub-10 µm for small dense parts; 50–150 µm for large components.

Detectable pore size≈2–3× voxel

Smallest reliably detected pore is roughly 2–3 voxels across. To find 20 µm pores, need ~7–10 µm voxel.

Max penetration (steel)≈40–70 mm

X-ray penetration limits part size/density. High-energy (450 kV / linac) systems penetrate dense titanium and steel; aluminium penetrates much further.

Scan + analysis time20 min – several h

Depends on resolution, part size, and number of projections. Production CT cells automate handling for serial inspection.

Compatible AM processes

Compatible materials

titanium alloysnickel alloysstainless steelaluminium alloyscobalt chrometool steels

Limitations

  • X-ray penetration limits part size and density — thick dense titanium/steel sections may exceed system capability
  • Resolution trades against part size — you cannot get fine voxel resolution on a large part in one scan
  • Capital-intensive and slower than surface metrology — typically a sampling or qualification tool, not 100% inline (except in automated production CT cells)
  • Beam-hardening and scatter artefacts require careful setup and calibration for quantitative porosity measurement
  • Detects defects but does not fix them — feeds HIP / accept-reject decisions

Providers

View all post-processing vendors →

Relevant standards

ASTM E1570ISO 15708ASTM E1441VDI VDE 2630

Resolution, penetration, and detectability figures from ZEISS, Nikon, Waygate (Baker Hughes), and North Star Imaging published CT specifications (manufacturer tier). Standards per ASTM E1570 / ISO 15708 / VDI-VDE 2630 (CT metrology).

All post-processing