1、Designation: E155 10E155 14Standard Reference Radiographs forInspection of Aluminum and Magnesium Castings1This standard is issued under the fixed designation E155; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.These Reference Radiographs have been developed in cooperation with the Quality Control Committee and Aerospace Research andTesting Comm
3、ittee of the Aerospace Industries Association.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 These reference radiographs illustrate the types and degrees of discontinuities that may be found in aluminum-alloy andmagnesium-alloy castings. The casting
4、s illustrated are in thicknesses of 14 in. (6.35 mm) and 34 in. (19.1 mm). The referenceradiograph films are an adjunct to this document and must be purchased separately from ASTM International if needed.1.2 These film reference radiographs are not intended to illustrate the types and degrees of dis
5、continuities found inaluminum-alloy and magnesium-alloy castings when performing digital radiography. If performing digital radiography ofaluminum-alloy castings, refer to Digital Reference Image Standard E2422. Magnesium-alloy digital reference images are notcurrently available from ASTM Internatio
6、nal. If performing digital radiography of magnesium-alloy castings, refer to DigitalReference Image Standard E2869.1.3 This document may be used where no other applicable document exists, for other material thicknesses for which it has beenfound to be applicable and for which agreement has been reac
7、hed between the purchaser and the manufacturer.1.4 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.5 This standard does not purpo
8、rt 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 regulatorylimitations prior to use.NOTE 1Vol I: The set of reference radiographs con
9、sists of 13 plates covering discontinuities in aluminum-alloy castings and 10 plates coveringdiscontinuities in magnesium-alloy castings. Each plate is held in an 812 by 11-in. (216 by 279-mm) cardboard frame and each plate illustrates eightgrades of severity for the discontinuity in approximately a
10、 2 by 2-in. (51 by 51-mm) area. The cardboard frames are contained in a 1012 by 1112-in. (267by 292-mm) ring binder. The reference radiographs are not impacted by this revision. There have been no revisions to the adjunct reference radiographssince original issue. The adjunct reference radiographs o
11、f any issue remain valid and may be used to this standard.Vol. II: The set of reference radiographs consists of four plates covering discontinuities in magnesium-alloy castings only. Each plate is held in an 812by 11-in. (216 by 279-mm) cardboard frame and illustrates eight grades of severity for th
12、e discontinuity (with the exception of discrete discontinuities,where only one example of each discontinuity is given).NOTE 2Reference radiographs applicable to aluminum and magnesium die castings up to 1 in. (25 mm) in thickness are contained in ReferenceRadiographs E505.2. Referenced Documents2.1
13、ASTM Standards:2E94 Guide for Radiographic ExaminationE505 Reference Radiographs for Inspection of Aluminum and Magnesium Die CastingsE1316 Terminology for Nondestructive ExaminationsE2422 Digital Reference Images for Inspection of Aluminum CastingsE2869 Digital Reference Images for Magnesium Castin
14、gs1 These reference radiographs are under the jurisdiction of ASTM Committee E07 on Nondestructive Testing and are the direct responsibility of Subcommittee E07.02on Reference Radiological Images.Current edition approved Sept. 1, 2010Oct. 1, 2014. Published September 2010October 2014. Originally app
15、roved in 1960. Last previous edition approved in 20052010as E155 - 05.E155 - 10. DOI: 10.1520/E0155-10.10.1520/E0155-14.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer
16、to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended 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 chang
17、es accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. Uni
18、ted States12.2 ASTM Adjuncts:Reference Radiographs for Inspection of Aluminum and Magnesium Castings:Volume I, Aluminum and Magnesium Castings3Volume II, Magnesium Castings43. Terminology3.1 DefinitionsDefinitions of terms used in this standard may be found in Terminology E1316.3.2 Definitions of Te
19、rms Specific to This Standard:3.2.1 The terms relating to discontinuities used in these reference radiographs are described based upon radiographicappearance.3.2.2 foreign materialsappear as isolated, irregular, or elongated variations of film density, not corresponding to variations inthickness of
20、material, nor to cavities. They may be due to the presence of sand, slag, oxide or dross, or metal of different density.3.2.3 gas holesappear as round or elongated, smooth-edged dark spots, occurring individually, in clusters, or distributedthroughout the casting.3.2.4 gas porosityrepresented by rou
21、nd or elongated dark spots corresponding to minute voids usually distributed through theentire casting.3.2.5 microshrinkage (feathery type)microshrinkage having an elongated appearance resembling feather-like streaks.3.2.6 microshrinkage (sponge type)microshrinkage having a spongelike appearance, an
22、d more massive and equiaxed than thefeathery type.3.2.7 reacted sand inclusionsappear on radiograph as “spotty segregation,” that is, sharply defined round light areas, about1 mm in diameter, and often with the rim lighter than the center. They are entrapped sand particles that underwent reaction wi
23、thmolten magnesium alloys containing zirconium (Note 3).3.2.8 segregationsappear as variations in film density which can be explained by segregation of elements of atomic numbersdifferent from that of the matrix.3.2.8.1 gravity segregationappears white on radiograph and may range from a mottling-typ
24、e effect through white-diffusedspots blending with the matrix, to a cloud-like appearance in more severe cases. They are agglomerations of particles precipitatedat temperatures above liquidus (Note 3).3.2.8.2 eutectic segregationtype of segregation is generally represented when a defect or discontin
25、uity develops duringsolidification and is fed with a near eutectic residual liquid rich with alloying elements that have a high X-ray attenuation. Oneexception to this enrichment as illustrated in Reference Radiographs E155 is flow line (or eutectic depletion), where there is a localimpoverishment o
26、f the alloying elements that have a high X-ray attenuation (Note 3).(1) eutectic segregationmicroshrinkage typetype of segregation develops when a microshrinkage develops duringsolidification, and is fed with residual liquid rich in dense alloying elements such as thorium. The area will show light o
27、n aradiograph (Note 3).(2) eutectic segregationpipe-shrink typetype of segregation develops during solidification when a pipe shrink forms and isimmediately filled with eutectic liquid rich in high X-ray attenuation alloying elements. The area shows light on a radiograph asa feathery or dendritic fe
28、ature (Note 3).(3) eutectic segregationhot-tear typetype of segregation develops during solidification when the hot tear that takes place isimmediately filled with liquid rich in alloying elements high in X-ray attenuation. The defect shows as white or light irregulardefined lines (Note 3).(4) eutec
29、tic depletionflow linetype of segregation develops when a section of a mold is filled by liquid and solidifies at thefront before liquid from another feed meets the solid front. A portion of the solid front then partially melts; otherwise, thediscontinuity would be a cold shut. Solidification begins
30、 after this remelt and the initial crystals are of high purity and contain fewerhigh-density alloying elements than the melt average. Since the metal is still flowing across these crystals, the composition aheadof this solidifying front is depleted. This depletion of the eutectic shows on the radiog
31、raph as a dark diffused line (Note 3).(5) oxide inclusions in magnesium alloys containing zirconiumshow on a radiograph as well defined light area of irregularshape and size resembling a radiograph of a compacted fine steel wool. It is composed of complex magnesium oxide film with highzirconium cont
32、ent, and, if present, rare earths and thorium oxides also. It is often associated with zirconium-rich particles.NOTE 3More detailed descriptions of these discontinuities can be found in the article, “New Reference Radiographs for MagnesiumAlloy Castings,”by B. Lagowski, published in the Journal of T
33、esting and Evaluation, Vol 2, No. 4, July 1974.3.2.9 shrinkage cavityappears as a dendritic, filamentary, or jagged darkened area.3.2.10 shrinkage porosity or sponge (nonferrous alloys)a localized lacy or honeycombed darkened area.3 Available from ASTM International Headquarters. Order Reference Rad
34、iograph No. RRE015501.4 Available from ASTM International Headquarters. Order Reference Radiograph No. RRE015502.E155 1424. Significance and Use4.1 These radiographs are intended for reference only but are so designed that acceptance standards, which may be developedfor particular requirements, can
35、be specified in terms of these radiographs. The illustrations are radiographs of castings that wereproduced under conditions designed to develop the discontinuities. The radiographs of the 14-in. (6.35-mm) castings are intendedto be used in the thickness range up to and including 12 in. (12.7 mm). T
36、he radiographs of the 34-in. (19.1-mm) castings areintended to be used in the thickness range of over 12 in. to and including 2 in. (51 mm). The grouping and system of designationsare based on considerations of the best practical means of making these reference radiographs of the greatest possible v
37、alue.4.2 Film DeteriorationRadiographic films are subject to wear and tear from handling and use. The extent to which the imagedeteriorates over time is a function of storage conditions, care in handling and amount of use. Reference radiograph films are noexception and may exhibit a loss in image qu
38、ality over time. The radiographs should therefore be periodically examined for signsof wear and tear, including scratches, abrasions, stains, and so forth.Any reference radiographs which show signs of excessive wearand tear which could influence the interpretation and use of the radiographs should b
39、e replaced.5. Basis for Application5.1 The reference radiographs may be applied as acceptance standards tailored to the end use of the product. Application ofthese reference radiographs as acceptance standards should be based on the intended use of the product and the followingconsiderations (see No
40、te 4).5.1.1 Compare the production radiographs of the casting submitted for evaluation with the reference radiographs applicable todesignated wall thickness in accordance with the written acceptance criteria.5.1.2 An area of like size to that of the reference radiograph shall be the unit area by whi
41、ch the production radiograph isevaluated, and any such area shall meet the requirements as defined for acceptability.5.1.3 Any combination or portion of these reference radiographs may be used as is relevant to the particular application.Different grades or acceptance limits may be specified for eac
42、h discontinuity type. Furthermore, different grades may be specifiedfor different regions or zones of a component.5.1.4 Special considerations may be required where more than one discontinuity type is present in the same area. Anymodifications to the acceptance criteria required on the basis of mult
43、iple discontinuity types must be specified.5.1.5 Where the reference radiographs provide only an ungraded illustration of a discontinuity, acceptance criteria may bespecified by referencing a maximum discontinuity size, or percentage of the discontinuity size illustrated.5.1.6 Production radiographs
44、 showing porosity, gas, shrinkage, or inclusions shall be evaluated by the overall condition withregard to size, number, and distribution. The aggregate size of discontinuities shall not exceed the total accumulation in area ofthe discontinuities of the reference radiograph. It is not the intent tha
45、t the maximum size of the illustrated discontinuity shall bethe limiting size for a single production radiographic discontinuity, or that the number of discontinuities shown on the referenceradiograph shall be the limiting number for production radiographs. Also, caution should be exercised in judgi
46、ng a largediscontinuity against a collection of small discontinuities on the basis of size alone. Each of the factors of size, number, anddistribution must be considered in balance. The purchaser may provide documented specific methods of evaluation.5.1.7 When the severity level of discontinuities p
47、er unit in the production radiograph being evaluated is equal to or better thanthe severity level in the specified reference radiograph, that part of the casting represented by the production radiograph shall beacceptable. If the production radiograph shows discontinuities per unit area of greater s
48、everity than the reference radiograph, thatpart of the casting shall not be accepted.5.1.8 As a minimum the acceptance criteria should contain information addressing: zoning of the part (if applicable), theacceptable severity level for each discontinuity type, and the specified area to which the ref
49、erence radiographs are to be applied.NOTE 4Caution should be exercised in specifying the acceptance criteria to be met in a casting. Casting design coupled with foundry practice shouldbe considered. It is advisable to consult with the manufacturer/foundry before establishing the acceptance criteria to ensure the desired quality level canbe achieved.6. Description6.1 The radiographs listed in Table 1 illustrate each type of discontinuity in eight grades. The radiographs listed in Table 2illustrate each type of discontinuity in eight grades, with th
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