1、Designation: E 272 99 (Reapproved 2004)e1Standard Reference Radiographs forHigh-Strength Copper-Base and Nickel-Copper AlloyCastings1This standard is issued under the fixed designation E 272; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, 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.e1NOTEEditorial changes were made throughout in May 2004.1. Scope1.1 These reference radiographs illustrate
3、various types anddegrees of discontinuities occurring in high-strength copper-base, nickel-copper, and related types of alloys. The referenceradiograph films are an adjunct to this document and must bepurchased separately from ASTM International, if needed.1.2 These reference radiographs are reprodu
4、ctions of origi-nal radiographs that contain indications of discontinuities insand-cast manganese-nickel-aluminum bronze-alloy plates.These discontinuities are representative of those found innarrow freezing range (formerly “high shrinkage”), high-strength copper and nickel-copper alloys.1.3 The val
5、ues stated in inch-pound units are to be regardedas the standard.1.4 This standard does not purport to address all of thesafety 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 appl
6、ica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B 148 Specification for Aluminum-Bronze Sand CastingsB 369 Specification for Copper-Nickel Alloy CastingsB 584 Specification for Copper Alloy Sand Castings forGeneral ApplicationsE94 Guide for Radiographic E
7、xaminationE 186 Reference Radiographs for Heavy-Walled (2 to 412-in. 51 to 114-mm) Steel CastingsE 192 Reference Radiographs of Investment Steel Castingsfor Aerospace ApplicationsE 446 Reference Radiographs for Steel Castings Up to 2 in.51 mm in ThicknessE 1316 Terminology for Nondestructive Examina
8、tions2.2 Military Specification:MIL-B-21230A Bronze, NickelAluminum and Manganese-Nickel Aluminum, Casting, Ship Propeller Application32.3 ASTM Adjuncts:Reference Radiographs for High-Strength Copper-Base andNickel-Copper Alloy Castings43. Terminology3.1 DefinitionsFor definitions of terms used in t
9、hisdocument, see Terminology E 1316.4. Significance and Use4.1 Reference radiographs for high-strength copper-baseand nickel-copper alloy castings are intended to be used as aguide to the recognition of common discontinuities and theirdifferentiation both as to type and severity level. A standarddes
10、cription of casting defects and corresponding radiographicindication types is available for reference in acceptance stan-dards, specifications, and drawings. Purchasers and suppliersmay, by mutual agreement, select particular radiographs toserve as standards representing minimum acceptability. Thest
11、andards so established are identified by an alphabetic defecttype and severity level (or class) designation.1These reference radiographs are under the jurisdiction of ASTM CommitteeE07 on Nondestructive Testing and are the direct responsibility of SubcommitteeE07.02 on Reference Radiological Images.
12、Current edition approved May 1, 2004. Published June 2004. Originallyapproved in 1965. Last previous edition approved in 1999 as E 272 - 99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volum
13、e information, refer to the standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-50984Available from ASTM Headquarters. Order RRE0272.1Copyright ASTM International, 100 Barr Harbor
14、 Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2 The following ASTM specifications illustrate alloys thatmay be used with these standards. It is intended that thesereference radiographs also apply to related government andcommercial material specifications.Alloys ASTM Specifi
15、cationsAAluminum Bronze B 148Nickel-Aluminum Bronze B 148Copper-Nickel B 369Manganese Bronze B 584Alloys Government SpecificationAManganese-Nickel-Aluminum Bronze MIL-B-21230AAlloy No. 2.Nickel-Copper MIL-B-21230AAlloy No. 2.ASee Section 2 for the complete title(s) of these specification(s).NOTE 1Th
16、e reference radiographs consist of forty-five 5 by 7-in. 127by 178-mm radiograph reproductions (twenty made from 1-in. 25.4-mmplate castings with low-voltage X-rays and twenty-five made from 3-in.76-mm plate castings with 2-MV X-rays or cobalt-60).4.3 The discontinuity types and severity levels repr
17、esentedby the reference radiographs are shown in Table 1, which alsoindicates the code designation for each discontinuity type.4.4 Discontinuity types most common to these alloys areillustrated. Other discontinuity types such as unfused insertsare illustrated in applicable Reference Radiographs E 44
18、6,E 186, and E 192.4.5 The use of this document is not intended to be restrictedto the specific energy levels given in Note 1 or to the thicknesslimits given in Table 1. The document may be used, wherethere is no other applicable document, for other energy levelsor thicknesses, or both, for which it
19、 is found to be applicableand for which agreement has been reached between purchaserand manufacturer.5. Descriptions of Discontinuities5.1 The following paragraphs are provided to aid in theidentification and classification of discontinuities. They brieflydescribe the radiographic appearance of comm
20、on types ofdiscontinuities and indicate their probable cause.5.1.1 Gas HolesAppear as round or elongated smooth-edged dark spots which may occur either individually, inclusters, or distributed throughout the casting section. They aregenerally caused by trapped air or mold gases.NOTE 2Discontinuities
21、 caused by evolved gases may occur as moreor less spherical voids, but may also occur as elongated “worm holes” orcavities somewhat resembling certain types of shrinkage. It is recom-mended that the “worm hole” cavities be evaluated by the use of thefeathery or spongy shrinkage category reference ra
22、diographs.5.1.2 ShrinkageShrinkage is generally associated withimproper feeding and manifests itself in the following differentindication forms:5.1.2.1 Sponge ShrinkageFound in heavier sections (gen-erally over 2 in. in thickness). It appears on the radiographs asa dark area or areas, lacy in textur
23、e, usually with a diffuseoutline.5.1.2.2 Feathery ShrinkageFound in thinner sections (un-der approximately 2 in.). It appears on radiographs as spongebut with a more feathery outline.5.1.2.3 Linear ShrinkageUsually a continuous structureof connected lines, branches or network of variable length,widt
24、h, and density.5.1.3 Hot TearsThe similarly appearing “hot tear” and“linear shrinkage” have distinctive characteristics. The follow-ing information is presented as a guide to interpreters tominimize confusion in distinguishing hot tears from linearshrinkage:5.1.3.1 Hot tears usually occur singly; sh
25、rinkage will gen-erally be multiple.5.1.3.2 Hot tears propagate at or near the surface; shrinkageappears to propagate at or near the midsection.5.1.3.3 Hot tears generally occur at hot spots or sectionchanges; linear shrinkage frequently occurs at uniform sectionsalso.5.1.3.4 Hot tears occur where t
26、emperature gradients arehigh; shrinkage occurs where temperature gradients are low.5.1.3.5 Hot tears occur transverse to the direction of greateststress.5.1.3.6 Hot tears can only be counteracted by altering thestress pattern or thermal pattern; shrinkage can always becountered by sufficient feed me
27、tal.5.1.4 Nonmetallic Inclusions:5.1.4.1 SandIrregularly, angularly shaped indications,more dense than the background, caused by clumps of trappedsand particles or pebbles.TABLE 1 Discontinuity Types and Severity Levels Illustrated bythe Reference RadiographsDiscontinuity Type CodeSeverity Levels or
28、 ClassesA,BUp to 2-in.Thickness2to6-in.ThicknessGas porosity A 1 through 5 1 through 5Sand inclusions Ba 1 through 5 1 through 5Dross inclusions Bb 1 through 5 1 through 5Shrinkage, linear Ca . 1 through 5Shrinkage, feathery Cd 1 through 5 .Shrinkage, spongy Cd . 1 through 5AThe radiographs of the 1
29、in. 25.4-mm thick plates are applicable to andinclude 2-in. 51-mm thick sections. The radiographs of the 3-in. 76-mm thickplates are recommended for sections over 2 and up to 6 in. 152 mm. However,upon agreement between manufacturer and purchaser they may be used for largersection thicknesses.BThe
30、discontinuity types are numbered according to severity level or class,Class 1 representing the highest quality castings.TABLE 2 Alloy Type Used to Produce Plate Castings for OriginalRadiographs(Composition MIL-B-21230A (SHIPS)Alloy No. 2)Chemical Composition, %Copper 71, minManganese 11 to 14Nickel
31、1.5 to 3.0Iron 2.0 to 4.0Aluminum 7.0 to 8.5Silicon 0.10, maxLead 0.03, maxOthers 0.50, maxMechanical PropertiesTensile strength, min, psi MPa 90 000 620Yield strength, min, psi MPa 40 000 275Elongation in 2 in. or 51 mm, min, % 20.0E 272 99 (2004)e125.1.4.2 DrossA series of lines in a swirl pattern
32、 some-times combined with agglomerated irregular indications. Drossis generally considered to represent oxidized metal.6. Description and Method of Preparation6.1 These reference radiographs were produced by the useof manganese-nickel-aluminum bronze plate castings. Table 2lists the chemical composi
33、tion and mechanical property limitsfor the alloy type. The references illustrate the appearance ofthe various radiographic severity levels when the originalradiographs are produced to an optical density of from 2.00 to2.25 on high-contrast, fine-grain film with a sensitivity (qualitylevel), as deter
34、mined by standard penetrameters, of 2 % (2-2T).5In selecting these reference radiographs, the aim was toobtain a progressively graduated series for each type ofdiscontinuity. It was not intended that like numbered levels orclasses be considered of equal severity (as far as deteriorationof mechanical
35、 properties is concerned) for the various catego-ries.6.2 The reproductions have been prepared to a density from2.00 to 2.25 and have retained substantially the contrast of theoriginal radiographs.7. Application of the Reference Radiographs7.1 In establishing acceptance standards, these referencerad
36、iographs may be used in full or in part, as desired.7.2 For each casting, the minimum acceptable severity level(or class) should be specified for each type of discontinuity; forexample, Severity Level 2 (or Class 2) might be specified forshrinkage (Type C) defects and Class 4 for gas porosity (TypeA
37、) defects, since the latter are generally much less deleterious.7.3 The acceptable quality level may vary in differentlocations of a casting, depending on the magnitude, directionand type of stress versus section contour.7.4 Production radiographs which are compared to thereference radiographs shoul
38、d have an optical density in the areaof interest in the range from 1.5 to 3.5 and a specified minimumsensitivity (quality level) of 2 % (2-2T).5Other quality levelsmay be designated, but then a suitable change in the severity orclass should be anticipated and hence specified. The recom-mended upper
39、density level of 3.5 for production radiographsis consistent with the capabilities of commonly availableviewing equipment. Radiographs of higher density are permit-ted if both producer and consumer have viewing equipmentwith adequately intense illuminators.7.5 Film DeteriorationRadiographic films ar
40、e subject towear and tear from handling and use. The extent to which theimage deteriorates over time is a function of storage condi-tions, care in handling and amount of use. Reference radio-graph films are no exception and may exhibit a loss in imagequality over time. The radiographs should, theref
41、ore, beperiodically examined for signs of wear and tear, includingscratches, abrasions, stains, and so forth. Any reference radio-graphs which show signs of excessive wear and tear whichcould influence the interpretation and use of the radiographsshould be replaced.8. Interpretation8.1 The following
42、 practice should be adhered to in evaluat-ing production radiographs of castings against the selectedstandard radiographs:8.1.1 When production radiographs, being evaluated withthe selected references in a particular contract, show disconti-nuities which are equal to or less severe than those in the
43、applicable reference radiographs, the casting shall be consid-ered radiographically acceptable. If the production radiographsshow a discontinuity of greater severity than the applicablereference radiograph, the casting shall be rejected until satis-factorily repaired (if permissible) (Section 9).8.1
44、2 If more than one type of discontinuity is revealed inthe same radiograph, the predominating type of defect aloneshall govern acceptability unless the severity represented bythe combination of discontinuity types is such as to make theoverall condition unacceptable for the intended application.8.1
45、3 When two or more categories of discontinuities arepresent to an extent equal to the maximum permissible level, asshown in the pertinent standards for each category, then thatpart of the casting shall be judged unacceptable until satisfac-torily repaired (if repairs are permissible) (see Section 9
46、).8.1.4 In general, there is no limit as to the extent ofacceptable discontinuities in a casting, provided that no 5 by7-in. 127 by 152-mm area throughout the casting containsdiscontinuities that exceed the severity of defects in theapplicable reference radiographs.8.1.5 Where the reference image co
47、nsists of a collection ofdiscontinuities, as in the case of porosity, for example, accept-ability may be based on 1) the aggregate size of the disconti-nuities present on both the reference radiograph and the objectradiograph, 2) the maximum defect size present, 3) the spacingbetween discontinuities
48、 or 4) a combination of these or othercriteria. These criteria must be determined based upon theparticular application or part under consideration and must bespecified by agreement between the purchaser and supplier.8.1.6 A diffraction mottling pattern can occur on films ofparts and sections where
49、the grain size is large enough to be anappreciable fraction of the material thickness (see Note 3). Ifdiffraction mottling is suspected, there are a number of ways todemonstrate its presence. The diffraction mottling patternshown in these cases is dependent principally upon the crystalgeometry and the orientation of the crystals to the incidentradiation. Therefore, for a given specimen, any change in thisorientation will effect the diffraction pattern dramatically. Thiscan be accomplished by a slight, 1 to 5 tilt of the part, withrespect to
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