1、Designation: B 594 06Standard Practice forUltrasonic Inspection of Aluminum-Alloy Wrought Productsfor Aerospace Applications1This standard is issued under the fixed designation B 594; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、 the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This practice covers t
3、he requirements for pulse-echoultrasonic inspection and includes criteria used to defineapplicable quality levels of aluminum-alloy wrought productsfor aerospace applications when performance of the ultrasonictest by the producer is specified, or when ultrasonic inspectionis performed by the purchas
4、er upon receipt.1.2 This practice is not applicable if plastic deformation isintroduced into the material after delivery.1.3 The ultrasonic test described in this practice is employedto detect internal discontinuities oriented in a direction parallelto, or nearly parallel to, the surface of the prod
5、uct. The test isperformed either by the immersion method or the contactmethod using pulsed longitudinal waves which are transmittedand received by a search unit containing either a single crystalor a combination of electrically interconnected multiple crys-tals. Ultrasonic tests employing either the
6、 through-transmissionor the angle-beam techniques are not included.NOTE 1Ultrasonic tests employing angle-beam techniques requirespecial reference blocks, search units, and scanning procedures and aresubject to negotiation between the purchaser and the seller when such testsare required by the contr
7、act or purchase order.1.4 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are mathemati-cal conversions to SI units which are provided for informationonly and are not considered standard.1.5 This standard does not purport to address all of the
8、safety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 The following documents of the issue in effe
9、ct on dateof material purchase form a part of this practice to the extentreferenced herein:2.2 ASTM Standards:2B 881 Terminology Relating to Aluminum- andMagnesium-Alloy ProductsE114 Practice for Ultrasonic Pulse-Echo Straight-BeamExamination by the Contact MethodE 127 Practice for Fabricating and C
10、hecking AluminumAlloy Ultrasonic Standard Reference BlocksE 214 Practice for Immersed Ultrasonic Testing by theReflection Method Using Pulsed Longitudinal Waves3E 317 Practice for Evaluating Performance Characteristicsof Ultrasonic Pulse-Echo Testing Instruments and Systemswithout the Use of Electro
11、nic Measurement Instruments2.3 American Society for Nondestructive Testing Standard:ASNT Recommended Practice for Nondestructive TestingPersonnel Qualification and CertificationUltrasonicTesting Method, SNT-TC-1A42.4 National Aerospace Standard:NAS-410 Certification of Inspection Personnel53. Termin
12、ology3.1 DefinitionsRefer to Terminology B 881 for definitionsof product terms used in this practice.4. Summary of Practice4.1 The product is inspected ultrasonically by scanningspecified entry surfaces with a beam of pulsed longitudinalwaves oriented in a direction perpendicular to the entrysurface
13、. The ultrasound is transmitted into the product either bythe direct contact or the immersion method. During the scan,indications representing discontinuities are displayed on anA-scan screen of the test instrument and may be detected byauxiliary electronic monitors, if used.1This practice is under
14、the jurisdiction of ASTM Committee B07 on LightMetals and Alloys and is the direct responsibility of Subcommittee B07.03 onAluminum Alloy Wrought Products.Current edition approved Nov. 1, 2006. Published December 2006. Originallyapproved in 1974. Last previous edition approved in 2002 as B 594 02.2F
15、or referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Available fromAmerican Society for Nondestructive T
16、esting (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.5Available from Aerospace Industries Association of America, Inc. (AIA), 1000Wilson Blvd., Suite 1700,Arlington, VA22209-3928, http:/www.aia-aerospace.org.1*A Summary of Changes section appears at the end o
17、f this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2 When the test system sensitivity level is appropriatelyadjusted, detected discontinuities and variations in back reflec-tion patterns are evaluated by comparing ampli
18、tudes of indi-cations with the ultrasonic responses from selected ultrasonicstandard reference blocks. The evaluated ultrasonic disconti-nuity responses are then classified and compared with appli-cable acceptance criteria.NOTE 2Additional information describing ultrasonic tests by thedirect contact
19、 method and by the immersion method is available inPractices E 114 and E 214.5. Significance and Use5.1 A number of factors such as the condition of the entryand back surfaces of the inspected part, the inclination of theultrasonic beam with respect to the entry surface, and varia-tions in the perfo
20、rmance characteristics of the test system maycause significant differences in amplitudes of discontinuityindications and back reflections. These factors can seriouslyimpair the reliability and the quantitative value of the ultra-sonic test outlined in this practice.5.2 Accurate evaluations of discon
21、tinuity size are alsosignificantly affected by variations in search unit characteristicsand by irregularities in discontinuity surfaces which caninfluence reflectivity. For these reasons, the discontinuity sizesthat may be implied by the ultrasonic comparisons outlined inthis practice must be regard
22、ed as “apparent” or “estimated” inrecognition of the limited quantitative value of the measure-ment.5.3 Because numerous interacting variables in a test systemcan adversely influence the results of an ultrasonic inspection,the actual quantitative effects of detected discontinuities uponthe mechanica
23、l properties of the inspected product are difficultto establish. Although this practice provides a reliable controlof product quality during manufacture, it is not applicable as anexclusive indicator of the ultimate quality and performance ofcomponents fabricated from the inspected products covered
24、bythis practice.6. Special Requirements6.1 When ultrasonic inspection of the finished product isrequired of the producer, purchase orders or contracts shallinclude the following information:6.1.1 Special Acceptance LimitsDiscontinuity class lim-its, if other than those defined in Section 11, shall b
25、e subject tonegotiation between the purchaser and the producer and shallbe in accordance with an agreement established between thepurchaser and the producer at the time of quotation oracceptance of purchase order or contract.6.1.2 Engineering DrawingsWhen ultrasonic inspectionis specified for alloys
26、, section thicknesses, and weights outsidelimits established in applicable product specifications, thespecial discontinuity class limits shall be as negotiated betweenthe purchaser and the producer and shall be indicated on zonedengineering drawings describing the material to be inspectedon part mac
27、hine drawings. The drawings shall also indicatenon-critical areas on the material and areas that will beremoved by machining.6.1.3 Special Testing ProceduresCylindrical sections orspecified areas of parts containing fillets may require additionalinspections employing special ultrasonic testing proce
28、dures(for example, angle-beam, shear-wave technique) not coveredby this practice. Such special testing procedures and accep-tance limits shall be established by negotiation and agreementbetween the purchaser and producer.7. Apparatus7.1 The required ultrasonic test system shall consist of thefollowi
29、ng:7.1.1 Basic Test InstrumentAny electronic device thatproduces electrical pulses to activate a search unit and displayspulses representing ultrasonic reflections on an A-scan screenis satisfactory if the minimum performance characteristicsspecified in 7.1.3 are met. The instrument shall provide st
30、ablelinear amplification of received pulses at a selected testfrequency and required sensitivity levels within the specifiedminimum performance limits.7.1.2 Search UnitThe recommended search unit is the flatnonfocusing type and contains a piezoelectric crystal whichgenerates and receives longitudina
31、l waves at the rated fre-quency when connected to the test instrument through asuitable coaxial cable. A dual-crystal search unit containingboth a transmitting and a receiving crystal in one container maybe used provided the test instrument will accommodate two-crystal operation. Special tests emplo
32、ying focusing search unitsmay be used provided such tests are established by negotiationand agreement between purchaser and producer.7.1.2.1 Search Unit SizeAny search unit of either circularor rectangular configuration may be used for initial scanning.For a circular configuration that provides an e
33、ffective crystalarea greater than 1.00 in.2(6.45 cm2) and for all rectangularsearch units a documented method of providing a uniformentry surface for the full extent of the sound beam shall beagreed upon between the purchaser and producer.Asearch unitcontaining a circular crystal of an effective dia
34、meter no greaterthan 0.75 in. (19.0 mm) is required to evaluate the ultrasonicresponse from detected discontinuities. When connected to thetest instrument and used for initial scanning and evaluatingresponses from discontinuities, the search unit shall meet orexceed the required minimum performance
35、characteristics atthe selected test frequency. Search units used only for initialscanning of a part prior to evaluation of suspect discontinuitiesshall, as a minimum, have adequate performance of sensitivityand signal to noise ratio appropriate to the class of inspectiondescribed in Section 11.NOTE
36、3The same search unit used for initial scanning may also beused for evaluating discontinuities provided its effective crystal diameteris no greater than 0.75 in. (19.0 mm) and minimum test systemperformance requirements are satisfied. Rectangular search units may beused for evaluation if the method
37、of use is established in writing by theproducer and approved by the purchaser.7.1.2.2 Effective Beam WidthThe effective beam width ofthe search unit shall be established by determining the totaltraverse distance over which response is maintained withinlimits specified below. The hole size in the sta
38、ndard PracticeE 127 reference block to be used for determining effectivebeam width shall be in accordance with those listed in Table 1for the applicable class of inspection. The metal distance of thereference block shall be that which produces the smallestB594062clearly resolved hole indication. The
39、 same water distance to beused for scanning shall be used to determine effective beamwidth.(a) For round search units, a maximum indication shall beobtained from the hole and then the instrument gain controlshall be adjusted to obtain a hole indication that is equal to80 % of the vertical limit. The
40、 effective beam width shall be thetraverse distance in the index direction over which the indica-tion from the flat-bottom hole equals or exceeds 40 % of thevertical limit.(b) For rectangular search units, an indication shall beobtained from the hole at any point along the longitudinal axisof the se
41、arch unit and then the instrument gain control shall beadjusted to obtain a hole indication that is equal to 80 % of thevertical limit. The effective beam width shall be the traversedistance in the index direction over which the indication fromthe flat-bottom hole equals or exceeds 40 % of the verti
42、callimit. The effective beam width establishes the maximumallowable index distance used during the initial scan sensitivityfor each inspection.7.1.2.3 Distance-Amplitude CharacteristicsThe distance-amplitude characteristics shall be established and recorded foreach search unit by obtaining the ultra
43、sonic response from acomplete distance-amplitude set of ultrasonic standard refer-ence blocks containing the No. 5 (0.078-in. diameter (1.98-mmdiameter) flat-bottomed holes (see 7.4) at a nominal sensitivitylevel to be used for evaluating the estimated size of detecteddiscontinuities. When using the
44、 search unit during testing, acheck of the established distance-amplitude characteristicsshall be conducted at least once per 8-h shift and shall beperformed by noting the ultrasonic response from at least threeselected No. 5 distance-amplitude reference blocks at theestablished sensitivity level. I
45、f the response from any blockdiffers by more than 610 % of the original distance-amplitudecurve established for the selected search unit, the performanceof the search unit shall be reevaluated and the test system shallbe restandardized to ensure proper conformance to the require-ments in this practi
46、ce, and all metal tested since the previousstandardization shall be retested.When testing metal to requirements that necessitate ultra-sonic reference standards other than No. 5 reference standardsfor inspection and/or evaluation (i.e., class AAA, AA, A, B, orC), it is acceptable to offset the dista
47、nce amplitude curve by abuilt-in or internally connected attenuator calibrated in deci-bels. Attenuators must affect only the return ultrasonic signal.Correction factors to be used after standardization on No. 5ultrasonic reference standards are shown in Table 2.NOTE 4The distance amplitude curve ma
48、y be established on one ormore sets of ultrasonic standard reference blocks, containing other thanNo. 5 flat bottomed holes, when justified by the inspection class of Section11.NOTE 5This section is not applicable when using the alternativeprocedure allowed by 10.5.2.7.1.2.4 Uniformity of Response f
49、or Rectangular SearchUnitsRectangular search units shall exhibit beam uniformitywithin 610 % of the mean amplitude of indication from theflat-bottomed hole during a traverse along the longitudinal axisof the search unit at the scanning sensitivity established withreference blocks for the applicable class (exclusive of end loberesponses).7.1.3 Test System PerformanceWhen used with appropri-ate auxiliary equipment described in subsequent paragraphs,the test system shall be capable of meeting or exceeding theminimum performance characteristics listed in Table 3 asdete
