Eddy current testing - material inspection
1. Identification of metal impurity content: purity is closely related to conductivity.
2. Identification of heat treatment state
Since the same material undergoes different heat treatments, not only the hardness but also the electrical conductivity, the method of measuring the conductivity can be used to indirectly evaluate the heat treatment state and hardness of the alloy.
3. Mixing and sorting
Conductivity measurement uses eddy current conductivity meter to measure the conductivity value of non-ferromagnetic metal. If the distribution of conductivity of hybrid materials or parts does not coincide with each other, the conductivity of the mixture is measured and then known. The material of the state or the conductivity of the component is compared to distinguish the mixture.
Eddy current thickness measurement
The eddy current detection method can be used to measure the thickness of the cladding on the metal substrate and the thickness of the metal thin plate, and the lift-off effect of the probe coil is utilized. The thickness is generally in the range of several micrometers to several hundred micrometers. The so-called lift-off effect refers to the influence of the change in the distance between the coil and the surface of the test material on the impedance of the coil.
When the thickness of the thin metal plate is measured by the eddy current method, the detecting coils may be arranged on the same side of the detected thin plate in a reflective operation manner, or may be arranged on both sides thereof in a projection manner. However, the thickness of the metal sheet is estimated based on the value of the induced voltage measured on the measuring coil. (责任编辑：admin) |
