What is one common application of Eddy current testing?

Eddy current testing is widely recognized for its effectiveness in detecting surface cracks in metal components. This non-destructive testing technique utilizes the principles of electromagnetism, where alternating current creates an electromagnetic field around a coil. When this field interacts with a conductive material, eddy currents are generated. These currents can be influenced by various factors, such as changes in the material's electrical conductivity or permeability, which can occur in the presence of surface defects like cracks.

When the eddy currents encounter a surface crack, the disruption in the flow of the current results in measurable changes in the impedance of the coil. Consequently, the testing equipment can identify these changes, indicating the presence of surface flaws. This application is particularly useful in industries where structural integrity is critical, such as aerospace and automotive, allowing for early detection of potential failures without causing any damage to the components being tested.

The other choices do not align with the primary functions of Eddy current testing. For instance, measuring temperature or evaluating the weight of metal parts typically requires different methodologies and tools. While assessing electrical insulation can be important in certain contexts, it is primarily addressed through other testing techniques that are specifically designed for that purpose.