ECHO-3D is an Electro-Magnetic Field (EMF) based technology that uses Electro-Magnetic Field Imaging (EMFI) to display surface breaking defects in a three-dimensional image.
The EMF is created by a focusing element which creates a large hemi elliptical toroidal field below the Sensor.
The EMF shape is measured in the X, Y and Z planes by specially shaped antenna coils.
Material permeability, conductivity, shape and distance from the surface to the sensor all affect the shape of the EMF.
ECHO-3D has the ability to cancel out these effects using a null command before scanning.
As the focused EMF from the Sensor passes over a surface breaking defect, such as a crack, SCC, or corrosion, the shape of the field is deformed.
The degree and location of the field shift is measured and the translated into crack location, direction and depth.
The material is not left with a residual magnetic field and therefore does not require degaussing prior to return to service.
Like UT, the ECHO-3D can detect a defect through a coating. Unlike UT, it does not require direct contact with the surface of the sample, nor does it require the use of a couplant.
ECHO-3D has demonstrated its ability to detect surface breaking cracks in both ferrous and non-ferrous materials.