1、Designation: E587 10E587 15Standard Practice forUltrasonic Angle-Beam Contact Testing1This standard is issued under the fixed designation E587; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in
2、parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This practice covers ultrasonic examination of materials by the pulse-echo technique, using continuous coupling of angularincident ultraso
3、nic vibrations.1.2 This practice shall be applicable to development of an examination procedure agreed upon by the users of the practice.1.3 The values stated in inch-pound units are regarded as standard. The values given in parentheses are mathematicalconversions to SI units that are provided for i
4、nformation only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regu
5、latorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E114 Practice for Ultrasonic Pulse-Echo Straight-Beam Contact TestingE317 Practice for Evaluating Performance Characteristics of Ultrasonic Pulse-EchoTesting Instruments and Systems without theUse of Electronic Measurement Ins
6、trumentsE543 Specification for Agencies Performing Nondestructive TestingE1316 Terminology for Nondestructive Examinations2.2 ASNT Documents:3SNT-TC-1A Recommended Practice for Nondestructive Testing Personnel Qualification and CertificationANSI/ASNT CP-189 Standard for Qualification and Certificati
7、on of Nondestructive Testing Personnel2.3 Military Standards:4MIL-STD-410 Nondestructive Testing Personnel Qualification and Certification2.3 Aerospace Industries Association Document:4NAS 410 Certification and Qualification of Nondestructive Testing Personnel2.4 ISO Standard:5ISO 9712 Non-Destructi
8、ve TestingQualification and Certification of NDT Personnel3. Terminology3.1 DefinitionsFor definitions of terms used in this practice,not specific to this standard, see Terminology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 group velocitythe sum of the individual waves collective
9、ly known as the pulse that travels through the material.3.2.2 phase velocitythe speed of the maximum wave point as it travels from one point to another in the material.1 This practice is under the jurisdiction ofASTM Committee E07 on Nondestructive Testing and is the direct responsibility of Subcomm
10、ittee E07.06 on Ultrasonic Method.Current edition approved June 1, 2010Dec. 1, 2015. Published July 2010December 2015. Originally approved in 1976. Last previous edition approved in 20052010 asE587 - 00E587 - 10.(2005). DOI: 10.1520/E0587-10.10.1520/E0587-15.2 For referencedASTM standards, visit the
11、ASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American Society for Nondestructive Testing (ASNT), P.O. Box 28518, 1711 Arlingate Ln
12、., Columbus, OH 43228-0518, http:/www.asnt.org.4 Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.4 Available from Aerospace Industries Association of America, Inc. (AIA), 1000 Wilson Blvd., Suit
13、e 1700, Arlington, VA 22209-3928, http:/www.aia-aerospace.org.5 Available from International Organization for Standardization (ISO), ISO Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva,Switzerland, http:/www.iso.org.This document is not an ASTM standard and is inte
14、nded only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the curre
15、nt versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Significance and Use4.1 An el
16、ectrical pulse is applied to a piezoelectric transducer which converts electrical to mechanical energy. In the angle-beamsearch unit, the piezoelectric element is generally a thickness expander which creates compressions and rarefactions. Thislongitudinal (compressional) wave travels through a wedge
17、 (generally a plastic). The angle between transducer face and theexamination face of the wedge is equal to the angle between the normal (perpendicular) to the examination surface and the incidentbeam. Fig. 1 shows the incident angle i, and the refracted angle r, of the ultrasonic beam.4.2 When the e
18、xamination face of the angle-beam search unit is coupled to a material, ultrasonic waves may travel in thematerial. As shown in Fig. 2, the angle in the material (measured from the normal to the examination surface) and mode ofvibration are dependent on the wedge angle, the ultrasonic velocity in th
19、e wedge, and the velocity of the wave in the examinedmaterial. When the material is thicker than a few wavelengths, the waves traveling in the material may be longitudinal and shear,shear alone, shear and Rayleigh, or Rayleigh alone. Total reflection may occur at the interface. (Refer to Fig. 3.) In
20、 thin materials(up to a few wavelengths thick), the waves from the angle-beam search unit traveling in the material may propagate in differentLamb wave modes.4.3 All ultrasonic modes of vibration may be used for angle-beam examination of material. The material forms and the probableflaw locations an
21、d orientations determine selection of beam directions and modes of vibration. The use of angle beams and theselection of the proper wave mode presuppose a knowledge of the geometry of the object; the probable location, size, orientation,and reflectivity of the expected flaws; and the laws of physics
22、 governing the propagation of ultrasonic waves. Characteristics ofthe examination system used and the ultrasonic properties of the material being examined must be known or determined. Somematerials, because of unique microstructure, are difficult to examine using ultrasonics. Austenitic material, pa
23、rticularly weldmaterial, is one example of this material condition. Caution should be exercised when establishing examination practices for thesetype materials. While examination may be possible, sensitivity will be inferior to that achievable on ferritic materials. Whenexamining materials with uniq
24、ue microstructures, empirical testing should be performed to assure that the examination will achievethe desired sensitivity. This may be accomplished by incorporating known reflectors in a mock up of the weld or part to beexamined. For material with such unique microstructures, a technique and proc
25、edure shall be agreed upon between contractingparties.4.3.1 Angle-Beam Longitudinal WavesAs shown in Fig. 4, angle-beam longitudinal waves with refracted angles in the rangefrom 1 to 40 (where coexisting angle-beam shear waves are weak, as shown in Fig. 3) may be used to detect fatigue cracks inaxle
26、s and shafts from the end by direct reflection or by corner reflection. As shown in Fig. 5, with a crossed-beam dual-transducersearch unit configuration, angle-beam longitudinal waves may be used to measure thickness or to detect reflectors parallel to theexamination surface, such as laminations. As
27、 shown in Fig. 6, reflectors with a major plane at an angle up to 40 with respect tothe examination surface, provide optimum reflection to an angle-beam longitudinal wave that is normal to the plane of the reflector.Angle-beam longitudinal waves in the range from 45 to 85 become weaker as the angle
28、increases; at the same time, the coexistingangle-beam shear waves become stronger. Equal amplitude angle beams of approximately 55 longitudinal wave and 29 shearwave will coexist in the material, as shown in Fig. 7. Confusion created by two beams traveling at different angles and at differentvelocit
29、ies has limited use of this range of angle beams.4.3.2 Angle-Beam Shear Waves (Transverse Waves)Angle-beam shear waves in the range from 40 to 75 are the most usedangle beams. They will detect imperfections in materials by corner reflection and reradiation (as shown in Fig. 8) if the plane ofthe ref
30、lector is perpendicular to a material surface, and by direct reflection if the ultrasonic beam is normal to the plane of thereflector (as shown in Fig. 9). Reflectors parallel to the examination surface (such as laminations in plate, as shown in Fig. 10) canrarely be detected by an angle beam unless
31、 accompanied by another reflector; for example, a lamination at the edge of a plate (asshown in Fig. 11) can be detected by corner reflection from the lamination and plate edge. Generally, laminations should bedetected and evaluated by the straight-beam technique. Angle-beam shear waves applied to w
32、eld testing will detect incompletepenetration (as shown in Fig. 12) by corner reflection, incomplete fusion (as shown in Fig. 13) by direct reflection (when the beamFIG. 1 RefractionE587 152angle is chosen to be normal to the plane of the weld preparation), slag inclusion by cylindrical reflection (
33、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 surface. Confusion createdby two beams at slightly
34、different angles, traveling at different velocities, has limited applications in this range of angle beams.4.3.3 Surface-Beam Rayleigh WavesSurface-beam Rayleigh waves travel at 90 to the normal of the examination surface onthe examination surface. In material greater than two wavelengths thick, the
35、 energy of the Rayleigh wave penetrates to a depth ofapproximately one wavelength; but, due to the exponential distribution of the energy, one half of the energy is within one-quarterwavelength of the surface. Surface cracks with length perpendicular to the Rayleigh wave can be detected and their de
36、pth evaluatedby changing the frequency of the Rayleigh wave, thus changing its wavelength and depth of penetration. Wavelength equalsvelocity divided by frequency.FIG. 2 Mode of VibrationFIG. 3 Effective Angles in the Steel versus Wedge Angles in Acrylic PlasticFIG. 4 AxleFIG. 5 ThicknessE587 1535Vf
37、Subsurface reflectors may be detected by Rayleigh waves if they lie within one wavelength of the surface.4.3.4 Lamb WavesLamb waves travel at 90 to the normal of the test surface and fill thin materials with elliptical particlevibrations. These vibrations occur in various numbers of layers and trave
38、l at velocities varying from slower than Rayleigh up tonearly longitudinal wave velocity, depending on material thickness and examination frequency. Asymmetrical-type Lamb waveshave an odd number of elliptical layers of vibration, while symmetrical-type Lamb waves have an even number of elliptical l
39、ayersof vibration. Lamb waves are most useful in materials up to five wavelengths thick (based on Rayleigh wave velocity in a thickspecimen of the same material). They will detect surface imperfections on both the examination and opposite surfaces. Centrallylocated laminations are best detected with
40、 the first or second mode asymmetrical Lamb waves (one or three elliptical layers). Smallthickness changes are best detected with the third or higher mode symmetrical or asymmetrical-type Lamb waves (five or moreelliptical layers). A change in plate thickness causes a change of vibrational mode just
41、 as a lamination causes a mode change. Themode conversion is imperfect and may produce indications at the leading and the trailing edges of the lamination or the thin area.FIG. 6 Angle LongitudinalFIG. 7 Coincident BeamsFIG. 8 CornerFIG. 9 Normal PlaneE587 1545. Basis of Application5.1 Purchaser-Sup
42、plier Agreements: The following items require agreement between using parties for this practice to be usedeffectively:5.1.1 Personnel QualificationIf specified in the contractual agreement, personnel performing examinations to this practiceshall be qualified in accordance with a nationally recognize
43、d NDT personnel qualification practice or standard such asFIG. 10 LaminarFIG. 11 Edge LaminationFIG. 12 Incomplete PenetrationFIG. 13 Incomplete FusionFIG. 14 Slag and PorosityE587 155ANSI/ASNT-CP-189, SNT-TC-1A, MIL STD-410, NAS-410,NAS-410, ISO 9712, or a similar document and certified by theemplo
44、yer or certifying agency, as applicable. The practice or standard used and its applicable revision shall be identified in thecontractual agreement between the using parties.NOTE 1MIL STD-410 is canceled and has been replaced with NAS-410, however, it may be used with agreement between contracting pa
45、rties.5.1.2 Qualification of Nondestructive AgenciesIf specified in the contractual agreement, NDT agencies shall be qualified andevaluated as described in Specification E543. The applicable edition of Specification E543 shall be specified in the contractualagreement.5.2 For material with unique mic
46、rostructures as described in 4.3, a technique and procedure shall be agreed upon betweencontracting parties.6. Apparatus6.1 A complete ultrasonic system shall include the following:6.1.1 InstrumentationThe ultrasonic instrument shall be capable of generating, receiving, amplifying, and displayinghig
47、h-frequency electrical pulses.6.1.2 Search UnitsThe ultrasonic search units shall be capable of transmitting and receiving ultrasonic waves in the materialat frequencies and energy levels necessary for discontinuity detection as determined by the standardization procedure. The searchunits are fitted
48、 with wedges in order to transmit ultrasonic waves into the examination object at the desired angle and mode ofoperation.6.1.3 CouplantA couplant, usually a liquid or semiliquid, is required between the face of the search unit and the examinationsurface to permit the transmission of ultrasonic waves
49、 from the search unit into the material under examination. Typical couplantsinclude glycerin, water, cellulose gel, oil, water-soluble oils, and grease. Corrosion inhibitors or wetting agents or both may beused. Couplants must be selected that are not detrimental to the product or the process. The couplant used in standardization shouldbe used for the examination. The standardization and examination surface temperatures should be within 625F (14C) to avoidlarge attenuation and velocity differences in the wedge material.6.1.3.1 The coupling mediu
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