Radiographic Testing vs. Acoustic Resonance Testing: Choosing the Right Method for Your Production Needs

Non-destructive testing (NDT) is essential for ensuring the structural integrity of components in manufacturing. But with so many methods available, how do you choose the right method? In this guide, we’ll compare two tests: Radiographic Testing (RT) and Acoustic Resonance Testing (ART).

Radiographic uses electromagnetic waves to create images of parts, while ART uses sound waves to analyse parts. Read on to discover the key differences and find out which method is best suited for your production environment.

What is Radiographic Testing (RT)?

Radiography involves creating radiographic images by using radiation to penetrate a test object and capture the resulting image on a detector. A typical setup places the object between the radiation source and the detector. The object is exposed to the radiation for a specific duration, allowing an image or radiograph to form. This image displays varying shades of gray, reflecting differences in the object's geometry, density, thickness, flaws, texture, and other characteristics enabling precise evaluation of structural integrity.

Modern systems include conventional radiography, digital radiography (DR), and advanced computed tomography (CT), which provides detailed 3D imaging for complex geometries. Widely applied in aerospace, manufacturing, electronics, and medical industries, RT ensures safety and quality by offering non-invasive analysis. Despite its high setup costs and stringent radiation safety requirements, advancements in digital technology, automation, and portable systems are enhancing its efficiency and accessibility, making it indispensable for critical inspections across industries.

While radiography is a very useful technique, it does not lend itself to general production inspection of manufactured components but rather is more suited for high-resolution defect characterisation.

Advantages of Radiographic Testing:

• Detailed internal imaging: RT provides clear images of internal structures, which is useful for identifying and characterization of surface and internal defects..

• Effective for dense materials: RT can penetrate thick materials like metals, making it useful for industries like aerospace and heavy manufacturing.

• Visual evidence: Radiographic images provide direct visual evidence of defects.

• Versatile Material Inspection: Applicable to metals, composites, ceramics, and even biological materials.

• Non-invasive: The component remains undamaged, making it ideal for quality control in production lines.

  
  

Limitations:

• Health and safety concerns: The use of radiation poses health risks to operators, requiring strict safety protocols and equipment.

• Slow and costly: Setup, exposure time, and image processing can take time, delaying production, and the cost of equipment and radiation safety measures is high.

• Requires skilled technicians: Interpreting radiographic images and handling radiation equipment requires specialised training, and can still be subject to operator bias.

• Thickness Limitation: Materials that are very dense or thick may require higher energy sources, which are not always feasible.

What is Acoustic Resonance Testing (ART)?

Acoustic Resonance Testing (ART) assesses the structural integrity of components by analyzing their resonance frequencies. Every material has its own unique frequency signature based on its geometry and composition. ART involves exciting the component with mechanical vibrations and measuring the resulting acoustic response. Resonance shifts can indicate defects like cracks, inclusions, or porosity.

RESONIKS enhances traditional ART methods with advanced AI, significantly improving the speed and accuracy of defect detection. By training AI models on defect-free parts, RESONIKS' system can quickly and precisely detect anomalies in new components. This AI-driven approach transforms ART into a fast, scalable solution suitable for modern production lines.

Advantages of RESONIKS Acoustic Resonance Testing:

• Fast and automated: ART provides real-time results, making it ideal for high-volume production environments.

• Versatile: ART works on a wide range of materials, from metals to composites, porous components, and even parts with rough surfaces.

• Cost-effective: With minimal equipment and no operator training required, ART is a more affordable solution than radiographic methods.

• Easily integrates into production lines: RESONIKS’ ART system can be seamlessly incorporated into automated inspection processes.

  
  

Limitations:

• Does not indicate the location of defects: ART does not provide the same level of detailed internal imaging as RT.

• Requires reference parts: AI-based ART systems need defect-free parts for training, which may not be ideal for one-off or highly customised testing scenarios.

Conclusion

When choosing between Radiographic Testing and Acoustic Resonance Testing, it’s essential to consider the specific needs of your production process. Radiographic Testing excels in detecting internal defects in dense materials and provides clear visual evidence, but it comes with significant safety, cost, and time drawbacks. For these reasons, it is more interesting for high-resolution defect characterisation and low-volume manufacturing. On the other hand, Acoustic Resonance Testing—especially with RESONIKS' AI-enhanced approach—offers a faster, safer, and more cost-effective solution for high-volume, automated production environments.

In industries where speed, safety, and scalability are critical, ART is a cutting-edge alternative that ensures consistent quality without the complexities of radiation-based testing.