What Is Nondestructive Testing?

There are some inconel finished last week, and they needed to be sent for ultrasonic testing. 

So we'd like to introduce what is the Nondestructive Testing.

What is the Nondestructive Testing?

The fundamental principle of NDT lies in utilizing physical phenomena to detect anomalies by analyzing changes in energy or signal interactions with the test object. These phenomena include mechanical wave propagation, electromagnetic induction, radiation absorption, and optical reflection, among others. By measuring how energy interacts with the material, NDT techniques identify deviations from normal conditions, indicating potential defects. 

Below picture is the principle diagram of electromagnetic testing :

Main Classifications of NDT and Key Differences

Conclusion

NDT techniques vary widely in their principles, applications, and capabilities. Ultrasonic testing excels at internal defect detection, electromagnetic methods focus on surface/near-surface issues in conductive/ferromagnetic materials, radiographic testing provides detailed internal images (with safety tradeoffs), and visual testing offers simplicity for surface inspections. The choice of technique depends on material type, defect location, accessibility, and industry requirements, ensuring safe and reliable assessment without damaging the test object.