Penetrant test is used to detect surface defects. It is possible to detect expected surface defects on all metallic and non-metallic materials.

Errors that are not exposed to the surface and whose surface clarity has been lost for any reason cannot be detected with this method. In the penetrant test, the defects must be exposed to the surface. If the surface cleaning is not done properly, it directly affects the result negatively.

Forged steels, steel pipes, bridges, buildings, steel castings, high-low pressure casting molds and precision castings are a few examples of materials that can be controlled by this method.