1、Designation: E155 14E155 15Standard 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. If performing digital radiography of magnesium-alloycastings, refer to Digital Reference
6、 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 reached between the purchaser and the manufacturer.1.4 From time to time, there may be minor chan
7、ges to the process for manufacturing of the reference radiograph adjunctmaterials. These changes could include changes in the films or processing chemicals used, changes in the dies or printing for thecardboard mats, etc.; however, in all cases, these changes are reviewed by the Illustration Monitor
8、ing Subcommittee and allreference radiographs are reviewed against a fixed prototype image to ensure that there are no changes to the acceptance levelrepresented by the reference radiographs. Therefore, the adjunct reference radiographs remain valid for use with this standardregardless of the date o
9、f production or the revision level of the text standard.1.5 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.1.6 This standard does
10、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 regulatorylimitations prior to use.NOTE 1Vol I: The set of reference radiog
11、raphs consists 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 approx
12、imately a 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 radi
13、ographs of 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 severi
14、ty for the 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 Docu
15、ments2.1 ASTM Standards:2E94 Guide for Radiographic Examination1 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 Oct. 1, 2014Sept.
16、1, 2015. Published October 2014September 2015. Originally approved in 1960. Last previous edition approved in 20102014as E155 - 10.E155 - 14. DOI: 10.1520/E0155-14.10.1520/E0155-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org
17、. For Annual Book of ASTM Standardsvolume information, refer 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 m
18、ay not be technically possible to adequately depict all changes 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 Har
19、bor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1E505 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 fo
20、r Magnesium Castings2.2 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 Definiti
21、ons of Terms 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 inthic
22、kness of 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 porosityrepresent
23、ed by round 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 appea
24、rance, and 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 re
25、action withmolten 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 mot
26、tling-type 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
27、discontinuity 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 localimpover
28、ishment of 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 sho
29、w light on aradiograph (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 on aradiograph (Note 3).(2) eutectic
30、segregationpipe-shrink typetype of segregation develops during solidification when a pipe shrink forms andis immediately filled with eutectic liquid rich in high X-ray attenuation alloying elements. The area shows light on a radiographas a feathery or dendritic feature (Note 3).(3) eutectic segregat
31、ionhot-tear typetype of segregation develops during solidification when the hot tear that takes placeis immediately filled with liquid rich in alloying elements high in X-ray attenuation. The defect shows as white or light irregulardefined lines (Note 3).(4) eutectic depletionflow linetype of segreg
32、ation 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 after this remelt and the initial c
33、rystals 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 radiograph as a dark diffused line (Note 3
34、).3 Available from ASTM International Headquarters. Order Reference Radiograph No. RRE015501.4 Available from ASTM International Headquarters. Order Reference Radiograph No. RRE015502.E155 152(5) oxide inclusions in magnesium alloys containing zirconiumshow on a radiograph as well defined light area
35、 of irregularshape and size resembling a radiograph of a compacted fine steel wool. It is composed of complex magnesium oxide film with highzirconium content, and, if present, rare earths and thorium oxides also. It is often associated with zirconium-rich particles.(2) eutectic segregationpipe-shrin
36、k 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 feature (Note 3).(3) eutectic segregationhot-tear typetype
37、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) eutectic depletionflow linetype of segregation develops when a
38、 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 after this remelt and the initial crystals are of high p
39、urity 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 radiograph as a dark diffused line (Note 3).(5) oxide inclusion
40、s 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 content, and, if present, rare earths and thorium oxides also
41、. 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 Testing and Evaluation, Vol 2, No. 4, July 1974.3.2.9 shri
42、nkage 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.4. Significance and Use4.1 These radiographs are intended for reference only but are so designed that acceptance standards, wh
43、ich may be developedfor particular requirements, can 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 th
44、ickness range up to and including 12 in. (12.7 mm). The 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 t
45、hese reference radiographs of the greatest possible value.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 fil
46、ms are noexception and may exhibit a loss in image quality 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 t
47、he interpretation and use of the radiographs should be 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 o
48、f the product and the followingconsiderations (see Note 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 t
49、he reference radiograph shall be the unit area by which 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 each 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
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