Radiographic Testing (RT)
Advanced X-ray and Gamma-ray inspection for comprehensive internal defect detection
How It Works
Radiation Passes Through
Radiation is passed through the material under test.
Material Interaction
Differences in material density and thickness affect how much radiation passes through.
Image Capture
A detector or film captures the transmitted radiation, producing an image where internal flaws appear as dark shadows or variations.
Two Radiation Sources
X-rays
Produced by a machine, offering controllable intensity and ideal for lab or portable setups.
Gamma rays
Emanate from radioactive isotopes such as Iridium-192 or Cobalt-60, perfect for remote areas without electrical power.
Four Imaging Methods
Film Radiography
Traditional method with permanent record on photographic film.
Computed Radiography (CR)
Uses imaging plates and scanners.
Digital Radiography (DR)
Real-time imaging with immediate results.
Computed Tomography (CT)
Creates 3D images for detailed visualization.
Why It Works
The effectiveness of radiography is based on how radiation interacts with matter through three key mechanisms:
Photoelectric Absorption
Radiation energy is fully absorbed by atoms, more significant in dense materials.
Compton Scattering
Radiation is partially scattered after interacting with atomic electrons, common in medium-density materials.
Pair Production
At very high energies, radiation transforms into particle pairs, used for thick or high-atomic-number materials.
These interactions depend on material density, thickness, and atomic composition—determining how radiation is absorbed and how defects appear on the image.
Radiographic Testing in Action
Advanced RT Equipment
Real-time Inspection
Detailed Result Analysis
Advantages
- Applicable to all types of materials (metallic and non-metallic)
- Detects both surface and internal defects
- Provides permanent visual records for traceability
- Excellent for inspecting thick materials and complex geometries
Limitations
- Relatively expensive due to radiation equipment and safety requirements
- Requires stringent radiation safety protocols and certified operators
- Does not reveal the exact depth of defects within the material
- Slower compared to some other NDT methods
- Access to both sides of the component is necessary for inspection
Practical Applications
Aircraft Components
Component and structure inspection
Pipeline Integrity
Weld and pipeline verification
Casting & Forging
Quality assessment
Pressure Vessels
Vessel and boiler inspection
Forensic Analysis
Material failure investigation
Security Screening
Cargo inspection systems