CEN/TC 138/WG 11 - Infrared thermographic testing

This document specifies a method and establishes guidelines for non-destructive testing using active thermography with laser excitation.
Active thermography with laser excitation is mainly applicable, but not limited, to different materials (e.g. composites, metals, ceramics) and to:
- the detection of surface-breaking discontinuities, particularly cracks;
- the detection of discontinuities located just below the surface or below coatings with an efficiency that diminishes rapidly with a few mm depth;
- the detection of disbonds and delamination parallel to the examined surface;
- the measurement of thermal material properties, like thermal diffusivity;
- the measurement of coating thickness.
The requirements for the equipment, for the verification of the system, for the surface condition of the test object, for the scanning conditions, for the recording, the processing and the interpretation of the results are specified. This document does not apply to the definition of acceptance criteria.
Active thermography with laser excitation can be applied in industrial production as well as in maintenance and repair (vehicle parts, engine parts, power plant, aerospace, etc.).

This document defines the procedures for non-destructive testing using active thermography.
These testing procedures can be applied to different materials (e.g. composites, metals and coatings) and are appointed, but not limited to the:
—   detection of discontinuities (e.g. voids, cracks, inclusions, delaminations);
—   determination of layer or part thicknesses;
—   determination and comparison of thermophysical properties.
This standard is describing data acquisition and analysis principles for active thermography and is giving an informative guideline for appropriate selection of the excitation source. Acceptance criteria are not defined in this standard.
Active thermography is applied in industrial production (e.g. compound materials, vehicle parts, engine parts, power plant parts, joining technology, electronic devices) and in maintenance and repair (e.g. aerospace, power plants, civil engineering).

This European Standard specifies the general principles for thermography of non-destructive testing. Thermographic testing is used for the detection and localization of discontinuities (e.g. cracks, delamination and inclusions) in different materials (e.g. composites, metals and coatings).
Usually a thermal stimulation is required. The choice of thermal stimulation depends on the application (e.g. type of material, geometry of test object, type of defects to be determined).
Acceptance criteria are not defined in this standard.

This Europen Standard establishes terms and definitions for thermographic testing.

This European Standard describes properties and requirements of infrared cameras used for thermographic testing for non-destructive testing.
This document gives also examples of excitation sources, the properties and requirements are described in application standards for active thermography.

This document specifies a method and establishes guidelines for non-destructive testing using active thermography with inductive excitation.
By using inductive heating of the test object, this active thermography method is suitable for inspecting test objects made of metals or other electrically conductive materials.
Such tests are conducted for:
-   the detection of surface-breaking discontinuities, particularly cracks; and
-   the detection of discontinuities located near the surface.
The functional principle of the defect detection can be based on a direct interaction of defect and excitation signal (defect selective) or an indirect interaction by using derivations of the applied heat flow.
For this purpose, active thermography with inductive excitation is conducted using different sources of excitation (inductors) in reflection and transmission configurations. Areas tested in one shot are typically between a few cm2 and a few hundred cm2, depending on the geometry of the used inductor. In dynamic configuration, larger areas can be tested.
Fields of application for active thermography with inductive excitation are to be found in industrial manufacturing and in maintenance (vehicle, drive system and power plant components, jointing technique, semi-finished products, etc.).
Active thermography with inductive excitation is also called inductive thermography or eddy-current excited thermography.