AFNOR

NON-DESTRUCTIVE
ASSOCIATED
STANDARDS TESTING
METHODS

G C
Valid Standards.

IN NI
NF EN 1330-4 NF EN ISO 2400 NF EN 17635

ST SO
Non-destructive testing - Terminology Non-destructive testing - Ultrasonic Non-destructive testing of welds -
- Part 4: Terms used in ultrasonic testing - Specification for calibration General rules for metallic materials

TE RA
testing block No. 1
ISO 5577

LT
NF EN 16018 NF EN ISO 7963 Non-destructive testing - Ultrasonic
Non-destructive testing - Terminology Non-destructive testing - Ultrasonic testing - Vocabulary

U
- Terms used in ultrasonic testing with testing - Specification for calibration
phased arrays block No. 2 EN ISO 18563-3
Non-destructive testing - Characte-
NF EN ISO 16810 NF EN 12668-1 rization and verification of ultrasonic
Non-destructive testing - Ultrasonic Non-destructive testing - Characte- phased array equipment - part 3:
testing - General principles rization and verification of ultrasonic Combined systems
testing equipment - Part 1: Instru-
NF EN ISO 16811 ments
Non-destructive testing - Ultrasonic
testing - Sensitivity and range setting NF EN 12668-2
Non-destructive testing - Characte-
NF EN ISO 16823 rization and verification of ultrasonic
Non-destructive testing- Ultrasonic testing equipment - Part 2: Probes
testing - Transmission technique
NF EN 12668-3
NF EN ISO 16826 Non-destructive testing - Characte-
Non-destructive testing - rization and verification of ultrasonic
Ultrasonic testing - Examination for testing equipment - Part 3: Combined
discontinuities perpendicular to the equipment
surface
NF EN 16392-2
NF EN ISO 16827 Non-destructive testing - Characte-
Non-destructive testing - Ultrasonic risation and verification of ultrasonic
testing - Characterization and sizing phased array equipment - Part 2:
of discontinuities Probes

NF EN ISO 16828 EN ISO 18563-1

Non-destructive testing - Ultrasonic Non-destructive testing - Characte-

 Ultrasonic testing (UT) is one of the most widely used non-

testing - Time-of-flight diffraction rization and verification of ultrasonic
technique as a method for detection phased array equipment - part 1: Instru-
and sizing of discontinuities ments
destructive test methods. It is based on the analysis of an
COFRENDEdition_March2016

ultrasound wave as it passes through the part being inspected.

Written by COFREND in conjunction with Anne-Marie Roy (AMRoy Consulting), Florian Le Bourdais et Pierre Calmon (CEA LIST). 
Photos credtis : CEA LIST, M2M.

Confédération Française pour les Essais Non Destructifs

Maison des END - 64 rue Ampère - 75017 Paris - France
Tel : + 33 (0)1 44 19 76 18 - Fax : + 33 (0)1 30 16 24 54
www.cofrend.com - cofrend@cofrend.com
ULTRASONIC TESTING  Fields of
Principle Operating mode application
ADVANTAGES
Ultrasonic testing works on the principle of an ultrasonic
wave transmitted through a part to be tested, which is
In reflection mode, this being the most common, the part is
inspected by moving an ultrasonic probe which functions
OF THE
Ultrasonic testing is one of the most
then analysed after it has interacted with the material. as both transmitter and receiver, along or above the MÉTHOD widely used NDE methods. It can be
There are many specific techniques based on this surface and collecting then analysing the signals received.
Volume method: as ultrasound penetrates deep into the used for a wide range of materials


general principle, depending on whether the wave is
transmitted or reflected, whether the transmitter and A distinction is made between contact tests, where the material, the method can be used to inspect materials of all and can be adapted to different part
receiver are combined or separate or according to the ultrasonic probe is positioned on the surface of the part thicknesses; geometries. It can be used to detect any
type and angle of the ultrasonic waves used. to which a couplant has been applied, and immersion type of flaw representing a discontinuity
tests, where the probe is moved at a certain distance The settings (such as the frequency used) offer great


in the mechanical properties (cracks,
The most common inspection method is the pulse echo from the part which is immersed in a fluid, generally water. sensitivity for a wide range of flaw dimensions and parts;
inclusions, porosities, etc.).
method, similar to that used in medical imaging. The The inspection may be either manual, where the probe is
moved by an operator, or automatic. A great number of modelling tools are available for the


transmitter and receiver (combined or separate) are
diagnosis and quantitative assessment of the efficiency of the It is used for detecting cracks in metallic
positioned on the same side of the part. The receiver
collects the echoes reflected or diffracted from any The choice of probe, its size, the frequency of the waves method; materials, weld inspection, composite
obstacles encountered by the wave, such as flaws, transmitted by it and the specific settings to be used materials testing (for the aeronautics
interfaces between the materials or even the surface of (delay laws for phased array probes) all determine the The methods can be adapted to the materials and geometry sector in particular), porosity detection,


the part. characteristics of the ultrasonic beam transmitted in the of the parts. It can be used to inspect most materials, metals etc.
part, and the ensuing sensitivity and spatial resolution or composite materials;
The devices used for wave transmission/reception, of the inspection. These characteristics are now often It is not only used for flaw detection
estimated by modelling at the design phase. A great wealth of information is provided by the test: precise


called «ultrasonic probes» are generally based on the but also for dimensional analysis
piezo-electric effect. The main element, the transducer, is location and size of the flaws and an image of the region
inspected; (thickness measurement), sorting and
composed of a piezo-electric element which converts an A diagnosis is made according to the analysis of the
signals received: echoes received from the reflection or characterizing materials (steel grade
electric signal into a mechanical vibration and vice versa.
diffraction of the incident beam will indicate the presence Phased array techniques available offering improved identification) or characterizing surface


Ultrasonic testing underwent a major development with
the advances made in phased array techniques using of a flaw. The time between the reception of the echo performance compared to conventional ultrasonic testing treatments (such as heat treatment).
electronically controlled arrays of piezo-electric probes and the energizing of the transmitter is called the time-of- methods;
in transmission or reception. This technology, which is flight. It indicates the location of the flaw, which is detected
according to the amplitude. The acquisition time window Quick and simple to use;


now commonly used, adapts the characteristics of the
transmitted wave, such as its focal point or its angle of is thus defined according to the area of the part being
inspected for flaws. Access to the part is only required from one side;


incidence, by applying electronic delays to the various
elements, calculated according to the purpose of the According to the application, the diagnosis may be
based on an amplitude exceeding a set threshold No chemical or radiological risks;


inspection. An area or volume may thus be scanned, or
the ultrasonic beam can be focused on the material at during scanning, or on a more in-depth analysis of the
A technique that is in constant evolution due to technological


varying depths using the same probe. echographic images of the area inspected. The screen
displays are of different types, B-Scan, C-Scan, etc. The innovations and active R&D.
The frequency of the ultrasonic waves used will vary amplitudes are always measured in comparison to a
according to the materials tested and the applications reference. The UT equipment is first calibrated on mock-
within a range of around 100 kHz to 20 MHz. The ups containing reference reflectors in order to define the
frequency used is the result of a compromise between detection thresholds.
the spatial resolution (the higher the frequency the higher
this will be) and the penetration depth (which decreases
in proportion to the frequency due to signal attenuation).
An inspection of a steel part will typically be performed at
Phased array probe application
frequencies of between 1 and 5 MHz.
Image of the ultrasonic beams transmitted by a phased array probe workin in continuous variable ange beam mode (results of a simulation)

Design of a robotized inspection method for laboratory use