NDT Method Selector
Ranked scorecard across seven inspection methods — CT scan, X-ray, UT, FPI, MPI, eddy current, and visual. Set your material, defect target, geometry, volume, and criticality; get detection limits, cost bands, and standard references.
Part context
Set to 0 for no flaw-size requirement.
Top recommendation
Full volumetric inspection; detects internal porosity, lack of fusion, cracks, and delamination. Gold standard for AM quality. Produces a full 3D map of the part interior.
All methods — ranked
Full volumetric inspection; detects internal porosity, lack of fusion, cracks, and delamination. Gold standard for AM quality. Produces a full 3D map of the part interior.
Pulse-echo or phased-array technique detects sub-surface and volumetric defects. Portable. Phased array (PAUT) improves coverage on complex surfaces.
2D projection image of internal structure. Good for detecting gross porosity, large lack-of-fusion defects, and inclusions. Faster and cheaper than CT.
Not applicable for this context
Capillary penetrant drawn into surface cracks; UV illumination reveals defects. Excellent sensitivity for fine surface cracks. Low cost.
Magnetic flux leakage reveals surface and near-surface discontinuities in ferromagnetic parts. Fast, inexpensive, high sensitivity for surface cracks.
Induced eddy currents detect conductivity changes from surface/near-surface cracks. Non-contact, fast, no surface preparation required. Good for production-line use.
Direct or aided visual examination for obvious surface defects, dimensional nonconformities, and gross material issues. First inspection step in any quality chain.
Detection capability reference
| Method | Surface | Near-surf. | Volumetric | Min flaw | Capital | Op. cost |
|---|---|---|---|---|---|---|
| CT Scan | ✓ | ✓ | ✓ | 0.05 mm | $$$$ | $$$ |
| X-ray / RT | — | ✓ | ✓ | 0.3 mm | $$$ | $$ |
| UT / PAUT | — | ✓ | ✓ | 0.1 mm | $$ | $$ |
| FPI / LPI | ✓ | — | — | 0.025 mm | $ | $ |
| MPI / MT | ✓ | ✓ | — | 0.025 mm | $ | $ |
| ECT | ✓ | ✓ | — | 0.1 mm | $$ | $ |
| Visual / VT | ✓ | — | — | 0.5 mm | $ | $ |
Sources: ASTM E1742, E1417, E1444, E2375, E426; ISO 17636, 17638, 17640; NASA-STD-6030; SAE AMS 2647.