ASTM E587-00(2005)
(Practice)Standard Practice for Ultrasonic Angle-Beam Examination by the Contact Method
Standard Practice for Ultrasonic Angle-Beam Examination by the Contact Method
SCOPE
1.1 This practice covers ultrasonic examination of materials by the pulse-echo technique, using continuous coupling of angular incident ultrasonic vibrations.
1.2 The values stated in inch-pound units are regarded as standard. The SI equivalents are in brackets and may be approximate.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:E587–00 (Reapproved 2005)
Standard Practice for
Ultrasonic Angle-Beam Examination by the Contact Method
This standard is issued under the fixed designation E587; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.4 Aerospace Industries Association Document:
NAS 410 Certification and Qualification of Nondestructive
1.1 This practice covers ultrasonic examination of materials
Testing Personnel
by the pulse-echo technique, using continuous coupling of
angular incident ultrasonic vibrations.
3. Terminology
1.2 The values stated in inch-pound units are regarded as
3.1 Definitions—For definitions of terms used in this prac-
standard. The SI equivalents are in brackets and may be
tice, see Terminology E1316.
approximate.
1.3 This standard does not purport to address all of the
4. Significance and Use
safety concerns, if any, associated with its use. It is the
4.1 An electrical pulse is applied to a piezoelectric trans-
responsibility of the user of this standard to establish appro-
ducer which converts electrical to mechanical energy. In the
priate safety and health practices and determine the applica-
angle-beam search unit, the piezoelectric element is generally
bility of regulatory limitations prior to use.
a thickness expander which creates compressions and rarefac-
tions.Thislongitudinal(compressional)wavetravelsthrougha
2. Referenced Documents
wedge (generally a plastic). The angle between transducer face
2.1 ASTM Standards:
and the examination face of the wedge is equal to the angle
E114 Practice for Ultrasonic Pulse-Echo Straight-Beam Ex-
between the normal (perpendicular) to the examination surface
amination by the Contact Method
and the incident beam. Fig. 1 shows the incident angle f, and
i
E317 Practice for Evaluating Performance Characteristics
the refracted angle f , of the ultrasonic beam.
r
of Ultrasonic Pulse-Echo Testing Instruments and Systems
4.2 When the examination face of the angle-beam search
without the Use of Electronic Measurement Instruments
unit is coupled to a material, ultrasonic waves may travel in the
E543 Specification for Agencies Performing Nondestruc-
material. As shown in Fig. 2, the angle in the material
tive Testing
(measured from the normal to the examination surface) and
E1316 Terminology for Nondestructive Examinations
3 mode of vibration are dependent on the wedge angle, the
2.2 ASNT Documents:
ultrasonic velocity in the wedge, and the velocity of the wave
SNT-TC-1A Recommended Practice for Nondestructive
in the examined material. When the material is thicker than a
Testing Personnel Qualification and Certification
few wavelengths, the waves traveling in the material may be
ANSI/ASNT CP-189 Standard for Qualification and Certi-
longitudinal and shear, shear alone, shear and Rayleigh, or
fication of Nondestructive Testing Personnel
4 Rayleigh alone. Total reflection may occur at the interface.
2.3 Military Standards:
(Refer to Fig. 3.) In thin materials (up to a few wavelengths
MIL-STD-410 Nondestructive Testing Personnel Qualifica-
thick), the waves from the angle-beam search unit traveling in
tion and Certification
the material may propagate in different Lamb wave modes.
4.3 All ultrasonic modes of vibration may be used for
angle-beam examination of material. The material forms and
This practice is under the jurisdiction of ASTM Committee E07 on Nonde-
the probable flaw locations and orientations determine selec-
structive Testing and is the direct responsibility of Subcommittee E07.06 on
tion of beam directions and modes of vibration. The use of
Ultrasonic Method.
angle beams and the selection of the proper wave mode
Current edition approved January 1, 2005. Published January 2005. Originally
approved in 1976. Last previous edition approved in 2000 as E587 - 00. DOI:
presuppose a knowledge of the geometry of the object; the
10.1520/E0587-00R05.
probable location, size, orientation, and reflectivity of the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
expected flaws; and the laws of physics governing the propa-
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
gation of ultrasonic waves. Characteristics of the examination
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
Available fromTheAmerican Society for NondestructiveTesting (ASNT), P.O.
Box 28518, 1711 Arlingate Lane, Columbus, OH 43228-0518.
4 5
AvailablefromStandardizationDocumentsOrderDesk,Bldg.4SectionD,700 AvailablefromAerospaceIndustriesAssociationofAmerica,Inc.,1250EyeSt.
Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS. NW, Washington D.C. 20005.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E587–00 (2005)
11) can be detected by corner reflection from the lamination
and plate edge. Generally, laminations should be detected and
evaluated by the straight-beam technique. Angle-beam shear
waves applied to weld testing will detect incomplete penetra-
tion (as shown in Fig. 12) by corner reflection, incomplete
fusion (as shown in Fig. 13) by direct reflection (when the
beam angle is chosen to be normal to the plane of the weld
preparation), slag inclusion by cylindrical reflection (as shown
in Fig. 14), porosity by spherical reflection, and cracks (as
shown in Fig. 15) by direct or corner reflection, depending on
their orientation. Angle-beam shear waves of 80 to 85° are
frequently accompanied by a Rayleigh wave traveling on the
FIG. 1 Refraction
surface. Confusion created by two beams at slightly different
angles, traveling at different velocities, has limited applications
system used and the ultrasonic properties of the material being
in this range of angle beams.
examined must be known or determined. Some materials,
4.3.3 Surface-Beam Rayleigh Waves—Surface-beam Ray-
because of unique microstructure, are difficult to examine
leigh waves travel at 90° to the normal of the examination
using ultrasonics. Austenitic material, particularly weld mate-
surface on the examination surface. In material greater than
rial, is one example of this material condition. Caution should
two wavelengths thick, the energy of the Rayleigh wave
be exercised when establishing examination practices for these
penetrates to a depth of approximately one wavelength; but,
type materials. While examination may be possible, sensitivity
duetotheexponentialdistributionoftheenergy,onehalfofthe
will be inferior to that achievable on ferritic materials. When
energyiswithinone-quarterwavelengthofthesurface.Surface
examining materials with unique microstructures, empirical
cracks with length perpendicular to the Rayleigh wave can be
testing should be performed to assure that the examination will
detected and their depth evaluated by changing the frequency
achieve the desired sensitivity. This may be accomplished by
of the Rayleigh wave, thus changing its wavelength and depth
incorporatingknownreflectorsinamockupoftheweldorpart
of penetration. Wavelength equals velocity divided by fre-
to be examined.
quency.
4.3.1 Angle-Beam Longitudinal Waves—As shown in Fig.
V
4, angle-beam longitudinal waves with refracted angles in the l5
f
range from 1 to 40° (where coexisting angle-beam shear waves
Subsurface reflectors may be detected by Rayleigh waves if
are weak, as shown in Fig. 3) may be used to detect fatigue
they lie within one wavelength of the surface.
cracks in axles and shafts from the end by direct reflection or
4.3.4 Lamb Waves—Lamb waves travel at 90° to the normal
by corner reflection. As shown in Fig. 5, with a crossed-beam
of the test surface and fill thin materials with elliptical particle
dual-transducer search unit configuration, angle-beam longitu-
vibrations.These vibrations occur in various numbers of layers
dinal waves may be used to measure thickness or to detect
and travel at velocities varying from slower than Rayleigh up
reflectors parallel to the examination surface, such as lamina-
to nearly longitudinal wave velocity, depending on material
tions. As shown in Fig. 6, reflectors with a major plane at an
thickness and examination frequency. Asymmetrical-type
angle up to 40° with respect to the examination surface,
Lamb waves have an odd number of elliptical layers of
provide optimum reflection to an angle-beam longitudinal
vibration, while symmetrical-type Lamb waves have an even
wave that is normal to the plane of the reflector. Angle-beam
number of elliptical layers of vibration. Lamb waves are most
longitudinal waves in the range from 45 to 85° become weaker
useful in materials up to five wavelengths thick (based on
as the angle increases; at the same time, the coexisting
Rayleigh wave velocity in a thick specimen of the same
angle-beam shear waves become stronger. Equal amplitude
material). They will detect surface imperfections on both the
angle beams of approximately 55° longitudinal wave and 29°
examination and opposite surfaces. Centrally located lamina-
shear wave will coexist in the material, as shown in Fig. 7.
tions are best detected with the first or second mode asym-
Confusion created by two beams traveling at different angles
metrical Lamb waves (one or three elliptical layers). Small
and at different velocities has limited use of this range of angle
thickness changes are best detected with the third or higher
beams.
mode symmetrical or asymmetrical-type Lamb waves (five or
4.3.2 Angle-Beam Shear Waves (Transverse Waves)—
more elliptical layers). A change in plate thickness causes a
Angle-beam shear waves in the range from 40 to 75° are the
change of vibrational mode just as a lamination causes a mode
most used angle beams. They will detect imperfections in
change. The mode conversion is imperfect and may produce
materials by corner reflection and reradiation (as shown in Fig.
indications at the leading and the trailing edges of the lamina-
8) if the plane of the reflector is perpendicular to a material
tion or the thin area.
surface, and by direct reflection if the ultrasonic beam is
normal to the plane of the reflector (as shown in Fig. 9).
5. Basis of Application
Reflectors parallel to the examination surface (such as lamina-
tions in plate, as shown in Fig. 10) can rarely be detected by an 5.1 Purchaser-Supplier Agreements: The following items
angle beam unless accompanied by another reflector; for require agreement between using parties for this practice to be
example, a lamination at the edge of a plate (as shown in Fig. used effectively:
E587–00 (2005)
FIG. 2 Mode of Vibration
FIG. 3 Effective Angles in the Steel versus Wedge Angles in Acrylic Plastic
FIG. 4 Axle
FIG. 6 Angle Longitudinal
FIG. 5 Thickness
FIG. 7 Coincident Beams
5.1.1 Personnel Qualification—If specified in the contrac-
NAS-410, however, it may be used with agreement between contracting
tual agreement, personnel performing examinations to this
parties.
practice shall be qualified in accordance with a nationally
5.1.2 Qualification of Nondestructive Agencies—If speci-
recognized NDT personnel qualification practice or standard
fied in the contractual agreement, NDT agencies shall be
such as ANSI/ASNT-CP-189, SNT-TC-1A, MIL STD-410,
qualified and evaluated as described in Practice E543. The
NAS-410, or a similar document and certified by the employer
applicable edition of Practice E543 shall be specified in the
or certifying agency, as applicable. The practice or standard
contractual agreement.
used and its applicable revision shall be identified in the
5.2 For material with unique microstructures as described in
contractual agreement between the using parties.
4.3, a technique and procedure shall be agreed upon between
NOTE 1—MIL STD-410 is canceled and has been replaced with contracting parties.
E587–00 (2005)
FIG. 12 Incomplete Penetration
FIG. 8 Corner
FIG. 13 Incomplete Fusion
FIG. 9 Normal Plane
FIG. 14 Slag and Porosity
FIG. 10 Laminar
FIG. 15 Cracks
FIG. 11 Edge Lamination
examination surface to permit the transmission of ultrasonic
6. Apparatus
waves from the search unit into the material under examina-
6.1 A complete ultrasonic system shall include the follow- tion. Typical couplants include glycerin, water, cellulose gel,
ing: oil, water-soluble oils, and grease. Corrosion inhibitors or
6.1.1 Instrumentation—The ultrasonic instrument shall be wetting agents or both may be used. Couplants must be
capable of generating, receiving, amplifying, and displaying selected that are not detrimental to the product or the process.
high-frequency electrical pulses. The couplant used in standardization should be used for the
6.1.2 Search Units—The ultrasonic search units shall be examination. The standardization and examination surface
capable of transmitting and receiving ultrasonic waves in the temperatures should be within 625°F [14°C] to avoid large
material at frequencies and energy levels necessary for discon- attenuation and velocity differences in the wedge material.
tinuity detection as determined by the standardization proce- 6.1.3.1 The coupling medium should be selected so that its
dure. The search units are fitted with wedges in order to viscosity is appropriate for the surface finish of the material to
transmit ultrasonic waves into the examination object at the be examined. The examination of rough surfaces generally
desired angle and mode of operation. requires a high-viscosity couplant. The temperature of the
6.1.3 Couplant—Acouplant, usually a liquid or semiliquid, material’s surface can change the couplant’s viscosity. As an
is required between the face of the search unit and the example, in the case of oil and greases, see Table 1.
E587–00 (2005)
TABLE 1 Suggested Viscosities—Oil Couplants
7.2.1 Angle-Beam Longitudinal and Shear Waves.
7.2.1.1 Distance Standardization—To locate reflectors ac-
NOTE 1—The table is a guide only and is not meant to exclude the use
of a particular couplant that is found to work satisfactorily on a particular curately within the production item, a distance standardization
surface.
is recommended, either in terms of the component’s dimen-
Approximate Surface Roughness Equivalent Couplant Viscosity, weight sions or the beam path. Reflections from concentric cylindrical
Average (Ra µin.) motor oil
surfaces, such as provided by some IIW blocks and the AWS
5 to 100 SAE 10
distance reference block, may be used to adj
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