Defect Detection Analysis with 3D Scanning Technology

Industrial Computed Tomography (CT) is gaining popularity as a comprehensive quality control tool in many fields and sectors for its non-destructive inspection properties. The technology also scans and collects data from complex parts with previously inaccessible characteristics and features, highlighting flaws before they become costly to resolve later in the production process. Cracks, voids, inclusions, and porosities can be identified and represented in a 3D visualization from a single scan.

Advancements for product development

  • Quickly identify internal defects from auto generated 3D renderings
  • Defects are color coded for volume, size, and location to provide comprehensive results with no guesswork
  • Increased product quality from fast feedback to production adjustments 
  • Parts remain intact and undamaged, retaining crucial information and decreasing scrap 

Finding and correcting part defects to ensure product quality is paramount to many industries where field failures can have devastating impacts. However, no manufacturer wants to scrap good parts or toss an entire bad batch. CT offers both design and production teams the solution to addressing defects without negatively impacting manufacturing or the end user.

How CT detects defects

In the process of identifying defects, automated porosity analysis visually represents the size of inclusions through various colors on a 3D rendering. This analysis aids in assessing the quality of a component.  Anomalies can be pinpointed by identifying Regions of Interest (ROIs) in addition to precise 3D renderings of the defects themselves.

Important considerations when using X-ray CT for defect analysis:

  • Defect size: In order to achieve higher resolution and accuracy, scans should be set to a 3x3x3 matrix of voxels. For example, a scan with a 50 µm resolution can detect defects as small as 150 µm in size. Different matrix settings can influence contrast, which helps with identifying defects within material.
  • Contrast sensitivity: The level of contrast required varies with defect size and impacts the overall results you’re able to achieve. Larger defects demand less contrast while smaller defects necessitate higher contrast for effective scan detection. 

Finding the balance between scan resolution and contrast is application dependent and requires careful consideration to optimize the inspection results.

Other defect detection technologies

The inspection technology you choose depends on the application and the desired data outcome. Part composition, size, density, and geometry are all factors that influence the best inspection method for your application.

Eddy Current Testing (ECT)

 Inducing eddy currents into conductive materials and measuring the resulting changes to defects like cracks or voids

  • Benefits
    • Non-destructive: allows for inspection without damaging the part
    • Portable equipment: allows for onsite inspection of large or immovable components
    • Fast inspection: suitable for high-volume production environments
  • Limitations: 
    • Material conductivity: less effective for non-conductive materials 
    • Surface condition: surface roughness, coatings, or paint layers may impact the effectiveness and accuracy of ECT
    • Depth limitation: commonly used for surface and near-surface inspections and does not penetrate to the center of a part to assess internal defects

Magnetic Particle Testing (MPT)

Defects are detected in the surface levels of ferromagnetic materials using magnetic fields.

  • Benefits
    • Versatile geometries: suitable for a variety of part shapes and sizes
    • Cost effective: MPT equipment can be less expensive compared to other NDT methods
    • Rapid inspection: inspections can be performed relatively quickly, making it a suitable option for field inspections and manufacturing environments
  • Limitations
    • Material type: this method is only suitable for ferromagnetic materials (iron, nickel, cobalt, etc.)
    • Depth limitation: commonly used for surface and near-surface inspections and does not penetrate to the center of a part to assess internal defects
    • Surface condition: samples must be properly cleaned and prepared before inspection can be completed to not interfere with magnetic fields


Defects are detected through temperature variations using infrared imaging 

  • Benefits
    • Non-destructive: allows for inspection without damaging the part
    • Large FOV: easily inspects large structures or systems in a single scan
    • Material flexibility: suitable for composite applications, welds, castings, or molded parts 
  • Limitations:
    • Depth limitation: commonly used for surface and near-surface inspections and does not penetrate to the center of a part to assess internal defects
    • Material transparency: best suited for opaque or semi-opaque materials: glass or transparent plastics often result in less accurate data
    • Environmental factors: ambient room temperature, humidity, or air movement can affect the thermal imaging results

Why choose industrial CT over other options?

Industrial CT scanning is the only non-destructive testing method that can reveal all internal features of a part. It is not limited to surface-level cracks or voids; the X-rays penetrate through the entire component and output a 3D render of the exact features detected. CT is suitable for many material types including metal, plastic, glass, and organic materials, making it a strong choice for many industrial applications. While startup costs can be higher with a CT system than other defect detection equipment, the longevity of the technology and its range of inspection capabilities lend it to be a better all around system.

  • Not limited to surface inspection
  • Fewer material limitations
  • Suitable for parts of complex or simple geometries
  • 3D visualization
  • Digital archiving of all scan data

Overall, industrial CT scanning offers unique advantages that make it an attractive choice for a wide range of industries, including aerospace, automotive, electronics, medical devices, and additive manufacturing. However, it's important to consider factors such as cost, inspection time, and specific inspection requirements when choosing the most appropriate NDT method for your application.

Request a complimentary scan to see what defects are hidden inside your samples. The RX Solutions North American Technical Center at our Plymouth, MN facility is home to our contract inspection division.