Magnetic particle testing is a very sensitive method for inspection of surface and near-surface defects. Through magetising the test specimens and  use of suitable test products very thin crack openings or surface pores as well as material separations can be visualised by use of the flux leakage.

Magnetic particle testing can be applied for all materials which are ferromagnetic. This concerns iron, nickel, cobalt as well as their alloys and finally steel (except austenitic steel).

With magentic particle testing material separations which are open to the surface such as

as well as near-surface material defects can be proved. The depth of provable defects depents on the stength of the magnetic field.

The application of magnetic particle testing is regulated by the international recognised standard EN ISO 9934.


GHT focusses on research, development and distribution of test products and test equipment for surface crack testing.

GHT test products are: