Non Destructive Testing or NDT groups together all the processes and techniques that make it possible to provide information on the integrity and health of a material or part at different stages of the manufacturing process without altering or destroying it. Indeed, if the part presents significant discontinuities, it can be considered to make repairs by welding or grinding (if authorised in the specifications). Otherwise, subsequent steps (heat treatment/finishing) can be saved.
There are four main non-destructive testing methods for this testing process : magnetic particle inspection (MPI), dye penetrant testing, X-ray and finally ultrasound (US). As La GTM France is committed to quality and customer satisfaction. It has introduced magnetic particle inspection (MPI). Ideed, this process consists of creating an intense magnetic feed inside a ferromagnetic material. When a defect is present in its path, the magnetic flux is deflected and creates a leak which, by attracting the particles (coloured or fluorescent) of a developer product, provides a particular signature characteristic of the defect. Magnetic particle inspection applies only to ferromagnetic parts. It can only detect open or slightly underlying discontinuities (about 1 mm) such as cracks or tapes for example.
