What is a characteristic of an eddy current testing probe?

The effectiveness of an eddy current testing probe is significantly influenced by the mounting material used in conjunction with the probe. This is because the electrical and magnetic properties of the mounting material can affect the eddy current generation and flow in the test material. If the mounting material is highly conductive or has a permeability different from that of the inspected material, it can distort the magnetic field and the eddy current patterns, leading to inaccurate measurements. Therefore, understanding the mounting material’s characteristics and its interaction with the eddy currents is crucial for ensuring accurate and reliable test results.

Other options suggest specific limitations or requirements that are not universally applicable to eddy current testing techniques. For instance, probes can be made from various materials depending on the specific application and are not restricted to steel. Additionally, eddy current testing can be conducted across a range of temperatures, not just high temperatures, making the second option misleading. Calibration is important for maintaining accuracy, but it does not mean that constant calibration is a characteristic of all probes used in every situation. Each of these factors emphasizes that while they are important, they do not directly address the foundational aspect of the probe's interaction with mounting materials like the correct choice does.