1、Designation: E 310 99 (Reapproved 2004)e1Standard Reference Radiographs forTin Bronze Castings1This standard is issued under the fixed designation E 310; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、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.e1NOTEEditorial changes were made throughout in May 2004.1. Scope
3、1.1 These reference radiographs are reproductions of origi-nal radiographs and illustrate various types and degrees ofdiscontinuities occurring in tin bronze and related types ofalloys. The reference radiograph films are an adjunct to thisdocument and must be purchased separately from ASTMInternatio
4、nal if needed. They are intended to provide thefollowing:1.1.1 A guide to the recognition of common discontinuitiesand their differentiation both as to type and severity level.1.1.2 A standard nomenclature for reference in acceptancestandards, specifications and drawings.1.1.3 A source of reference
5、radiographs from which manu-facturers and purchasers may, by mutual agreement, selectparticular radiographs to serve as standards representing mini-mum acceptability. The standards so established are identifiedby an alphabetic defect type and severity level (or class)designation.1.2 The original rad
6、iographs are of discontinuities in sandcast 88:8:4 Cu-Sn-Zn, “G” type, bronze alloy plates. Thesediscontinuities are representative of those found in widesolidification range copper-tin base alloys. The followingASTM specifications illustrate alloys covered by these stan-dards; however, it is intend
7、ed that these reference radiographsalso apply to related Government and commercial materialspecifications:Valve bronze castings B 61AComposition bronze or ounce metal castings B 62BTin bronze sand castings B 584Leaded red brass sand castings B 584Copper-base alloy centrifugal castings (as applicable
8、) B 271ASimilar to MIL-B-16541.BSimilar to MIL-B-16444.1.3 The discontinuity types and severity levels representedby the reference radiographs are shown in Table 1, which alsoindicates the code designation for each discontinuity type.1.4 The use of this document is not intended to be restrictedto th
9、e specific energy level or to the absolute thickness limitsthat are contained in the document title. The title is intended tobe descriptive and not restrictive. The document may be used,where there is no other applicable document, for other energylevels or thicknesses, or both, for which it is found
10、 to beapplicable and for which agreement has been reached betweenpurchaser and manufacturer.NOTE 1The reference radiographs consist of twenty-two 212 by512-in. 63.5 by 139.7-mm radiograph reproductions of low voltage Xrays. Fifteen of these were made with newly developed 1-in. 25.4 mmplate castings
11、and seven were made with34-in. plate castings usedoriginally for documents NAVSHIPS 250-537-1 and -2. The new platecastings cover Gas Porosity, Linear Shrinkage, and Feathery Shrinkagediscontinuity types.1.5 The values stated in inch-pound units are to be regardedas the standard.1.6 This standard do
12、es 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 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Sta
13、ndards:2B 61 Specification for Steam or Valve Bronze CastingsB 62 Specification for Composition Bronze or Ounce MetalCastingsB 271 Specification for Copper-Base Alloy CentrifugalCastingsB 584 Specification for Copper Alloy Sand Castings forGeneral ApplicationsE 94 Guide for Radiographic ExaminationE
14、 1316 Terminology for Nondestructive Examinations2.2 ASTM Adjuncts:Reference Radiographs for Tin Bronze Castings31These reference radiographs are under the jurisdiction of ASTM CommitteeE07 on Nondestructive Testing and is the direct responsibility of SubcommitteeE07.02 on Reference Radiographs.Curr
15、ent edition approved May 1, 2004. Published June 2004. Originallyapproved in 1966. Last previous edition approved in 1999 as E 310 - 99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume in
16、formation, refer to the standards Document Summary page onthe ASTM website.3Available from ASTM International Headquarters. Order RRE0310.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3. Terminology3.1 DefinitionsFor definitions of
17、 terms used in this docu-ment, see Terminology E 1316, Section D.4. Significance and Use4.1 These reference radiographs were produced by the useof 88:8:4, Cu-Sn-Zn, “G” plate castings. Table 2 lists thechemical composition and mechanical property limits for thealloy type. The references illustrate t
18、he appearance of thevarious radiographic severity levels when the original radio-graphs are produced to an optical density of 2.0 6 0.2 on highcontrast, fine grain film with a sensitivity (quality level), asdetermined by standard penetrameters, of 2 % (2-2T). Inselecting these reference radiographs,
19、 the aim was to obtain aprogressively graduated series for each type of discontinuity(Note 2). It was not intended that alike numbered levels orclasses be considered of equal severity (as far as deteriorationof mechanical properties is concerned) for the various catego-ries.NOTE 2For a description o
20、f sensitivity or quality levels, see GuideE 94.4.2 The reproductions have been prepared to an H and Ddensity of 2.0 6 0.2 and have retained substantially thecontrast of the original radiographs. Details of the techniqueused in the original radiography are listed in Table 3. Thesedata are presented a
21、s a matter of record and are not to beconstrued as the only recommended techniques to be used forthe radiography of castings to be evaluated by these references.4.3 Film DeteriorationRadiographic films are subject towear and tear from handling and use. The extent to which theimage deteriorates over
22、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 therefore be peri-odically examined for signs of wear and tear, includingscratches, abrasions, stains,
23、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.5. Descriptions of Discontinuities5.1 The following paragraphs are provided to aid in theidentification and classification of disc
24、ontinuities (Note 3).They briefly describe the radiographic appearance of commontypes of discontinuities and indicate their probable cause.5.1.1 Gas HolesRound or elongated, smooth-edged darkspots which may occur either individually, in clusters, ordistributed throughout the casting section. They ar
25、e generallycaused by trapped air or mold gases.NOTE 3Discontinuities 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
26、 by the use of thefeathery or sponge shrinkage category reference radiographs.5.1.2 ShrinkageShrinkage is generally associated withimproper feeding and manifests itself in the following differentindication forms:5.1.2.1 Linear ShrinkageUsually a continuous structureof connected lines, branches or ne
27、twork of variable length,width, and density.5.1.2.2 Feathery ShrinkageAppears on the radiographs assponge but with a more feathery outline.5.1.2.3 Sponge ShrinkageAppears on the radiographs as adark area or areas, lacy in texture, usually with a diffuseoutline.5.1.3 Hot TearsThe similarly, appearing
28、 “hot tear” and“linear shrinkage” have distinctive characteristics. The follow-ing information is presented as guide to interpreters to mini-mize confusion in distinguishing hot tears from linear shrink-age:5.1.3.1 Hot tears usually occur singly; shrinkage will gen-erally be multiple.5.1.3.2 Hot tea
29、rs 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 temperature gradients arehigh; shrinkage occurs wher
30、e 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 metal.TABLE 1 Discontinuity Types and Severity Levels
31、 Illustrated bythe Reference RadiographsADiscontinuity Type CodeSeverity Level orClassesBBased on1-in. 25.4-mm ThickPlatesGas porosity A 1 to 5Sand inclusionsCB 1 to 5Shrinkage, linear Ca 1 to 5Shrinkage, feathery or spongy Cd 1 to 5Hot tearCDa 1 illustrationInserts, chapletsCEb 1 illustrationAThe r
32、adiographs are applicable to and including 2-in. thick sections. Uponagreement between manufacturer and purchaser, they may be used for largersection thicknesses.BThe discontinuity types are numbered according to severity level or class, onerepresenting the highest quality.CStandards are taken from
33、NAVSHIPS 250-537-1.TABLE 2 Alloy Type Used to Produce Plate Castings for OriginalRadiographsChemical Composition, %min maxCopper 86.00 89.00Tin 7.50 9.00Zinc 3.00 5.00Nickel . 1.00Lead . 0.30Iron . 0.15Phosphorus . 0.05Mechanical PropertiesTensile strength, min, psi MPa 40 000 275Elongation in 2 in.
34、 or 51 mm, min, 20E 310 99 (2004)e125.1.4 Nonmetallic Inclusions:5.1.4.1 SandIrregularly, angularly shaped indicationsmore dense than the background, caused by clumps of trappedsand particles or pebbles.5.1.4.2 DrossA series of lines in a swirl pattern, some-times combined with agglomerated irregula
35、r indications. Drossis generally considered to represent oxidized metal.6. Application of the Reference Radiographs6.1 In establishing acceptance standards, these referenceradiographs may be used in full or in part, as desired.6.2 For each casting, the minimum acceptable severity level(or class) sho
36、uld be specified for each type of discontinuity; forexample, the Severity Level 2 (or class) might be specified forshrinkage (Type C defects) and Class 4 for gas porosity (TypeA defects), since the latter are generally much less deleterious.6.3 The acceptable quality level may vary in differentlocat
37、ions of a casting depending on the magnitude, direction,and type of stress versus section contour.6.4 Production radiographs which are compared to thereference radiographs should have a film density in the area ofinterest in the range from 1.5 to 3.5 and a specified minimumsensitivity (quality level
38、) of 2 % (2-2T). Other quality levelsmay be designated, but then a suitable change in the severity orclass should be anticipated and hence specified. Radiographs ofhigher density are permitted if both manufacturer and pur-chaser have viewing equipment with adequately intense illu-minators.7. Interpr
39、etation7.1 The following practice should be adhered to in evaluat-ing production radiographs of castings against the selectedstandard radiographs.7.1.1 When production radiographs being evaluated withthe selected references show a discontinuity type which isequal to or less severe than those in the
40、applicable referenceradiographs, the casting shall be considered radiographicallyacceptable. If the production radiographs show a discontinuityof greater severity than the applicable reference radiograph, thecasting shall be rejected until satisfactorily repaired, if repair-ing is permissible (Secti
41、on 8).7.1.2 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 applic
42、ation.7.1.3 When two or more categories of discontinuity 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 Se
43、ction 8).7.1.4 In general, there is no limit as to the extent ofacceptable discontinuities in a casting, provided that no 212 by512-in. 63.5 by 139.7-mm area throughout the casting con-tains discontinuities that exceed the severity of defects in theapplicable reference radiographs.7.1.5 Where the re
44、ference image consists of a collection ofdiscontinuities, as in the case of porosity, for example, accept-ability may be based on the aggregate size of the discontinui-ties present on both the reference radiograph and the objectradiograph, the maximum defect size present, the spacingbetween disconti
45、nuities, or 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.7.1.6 A diffraction mottling pattern can occur on films ofparts and sections wh
46、ere the grain size is large enough to be anappreciable fraction of the material thickness (see Note 4). 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 a
47、nd 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 the radiation beam or simply by shifting thecente
48、rline of the radiation beam to a slightly different locationfrom the first exposure. Indications from any porosity, shrink-age or other discontinuity will move only slightly, while anymottling patterns present will change dramatically. If it isnecessary or desirable to eliminate the mottling, the kV
49、 may beraised to reduce the amount of diffraction radiation. However,caution should be used so that the kV is not raised to the pointthat sensitivity is reduced excessively. If diffraction mottling isdemonstrated to be present on a radiograph, this condition shallnot be considered as prejudicial in evaluating the radiograph.NOTE 4Mottling is often associated with thin sections of austeniticsteels and copper base alloys such as copper nickel, tin bronzes, and nickelcopper. Demonstration of mottling has also been shown in the duplexalloys as well.8. Repai
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