MAGNETIC PARTICLE INSPECTION

CRACK INSPECTION - (MT)

magnetic particle inspection

is a method for detecting cracks in and/or near the surface of ferromagnetic materials. During crack testing, the workpiece is magnetized either completely or partially, depending on its size.

The resulting field lines run parallel to the surface. Cracks and surface defects that lie perpendicular to the field lines generate a magnetic stray field (see figure below) (Fig. 1).

The field lines emerge in front of the defect and then re-enter the material, creating magnetic poles. If iron particles are then distributed on the surface, they accumulate at the defect or at the field lines of the stray field.

Defects running parallel to the field lines (Fig. 1) and located below the surface cannot be detected.

AREA OF APPLICATION

The magnetic particle method or crack testing (MT) is particularly suitable for detecting surface defects in complex, functionally and safety-critical steel or cast iron components with irregular geometries.

STANDARDS

DIN EN 9712 Training and qualification of personnel

DIN EN ISO 9934-1 Magnetic particle testing/crack testing or crack testing MT; general principles DIN EN ISO 9934-2

Magnetic particle testing/crack testing or crack testing MT; testing equipment DIN EN ISO 9934-3

Magnetic particle testing/crack testing or crack inspection MT; Equipment DIN EN ISO 30 59

MT and PT crack testing; Observation conditions DIN EN 1290

Crack testing or crack inspection MT of welded joints DIN 54 130

Magnetic flux leakage method