1、Designation: E2973 15Standard Digital Reference Images forInspection of Aluminum and Magnesium Die Castings1This standard is issued under the fixed designation E2973; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These digital reference images illustrate variouscategories, types, and severity levels of discontinuities thatmay occur i
3、n aluminum-alloy and magnesium-alloy die cast-ings. They are intended to provide:1.1.1 A guide enabling recognition of discontinuities andtheir differentiation both as to type and severity level throughdigital radiographic imaging.1.1.2 Example digital radiographic illustrations of disconti-nuities
4、and a nomenclature for reference in acceptancestandards, specifications, and drawings.NOTE 1The basis of application for these reference images requires aprior purchaser supplier agreement of radiographic examination attributesand acceptance criteria as described in Sections 5 and 6 of this standard
5、.1.2 These digital reference images consist of nine imagescovering discontinuities in aluminum and magnesium alloy diecastings. Four contain graded sequences of four levels ofincreasing severity in aluminum castings. Four contain gradedsequences of four levels of increasing severity in magnesiumcast
6、ings. The last image contains ungraded illustrations ofinclusions in aluminum and magnesium alloy die castings.1.3 Two kinds of illustration categories are covered asfollows:1.3.1 GradedThree discontinuity categories for aluminumdie castings and three discontinuity categories for magnesiumdie castin
7、gs, each illustrated in four levels of progressivelyincreasing severity. Category A discontinuities are illustratedfor aluminum and magnesium die castings having thicknessesof18 in. (3.2 mm) and58 in. (15.9 mm); Category Bdiscontinuities are illustrated for18 in. thick aluminum andmagnesium die cast
8、ings; and Category C discontinuities areillustrated for58 in. (15.9 mm) thick aluminum and magnesiumdie castings.1.3.2 UngradedOne illustration of one discontinuity for0.20 in. (5.1 mm) thickness aluminum die casting and oneillustration of one discontinuity for18 in. (3.2 mm) thicknessmagnesium die
9、casting.1.4 This document may be used for other materials, thick-nesses or with other energy levels for which it has been foundto be applicable and agreement has been reached betweenpurchaser and supplier.1.5 All areas of this standard may be open to agreementbetween the cognizant engineering organi
10、zation and thesupplier, or specific direction from the cognizant engineeringorganization. These items should be addressed in the purchaseorder or the contract.1.6 These digital reference images are not intended toillustrate the types and degrees of discontinuities found inaluminum and magnesium die
11、castings when performing filmradiography. If performing film radiography of aluminum ormagnesium die castings, refer to Reference Radiographs E505.1.7 Only licensed copies of the software and images shall beutilized for production inspection. A copy of the ASTM/Userlicense agreement shall be kept on
12、 file for audit purposes. (SeeNote 2.)NOTE 2The set of digital reference images consists of nine digital datafiles, and software to load the desired format and specific instructions onthe loading process. The nine reference images illustrate eight sets ofgraded discontinuities and one category of un
13、graded discontinuities.Available from ASTM International Headquarters, Order No: RRE2973.1.8 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units.1.9 This standard does not purport to address all of thesafety con
14、cerns, 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 Standards:2E505 Reference Radiographs for Inspect
15、ion of Aluminumand Magnesium Die CastingsE1316 Terminology for Nondestructive Examinations1This test method is under the jurisdiction of ASTM Committee E07 onNondestructive Testing and is the direct responsibility of Subcommittee E07.02 onReference Radiological Images.Current edition approved Jan. 1
16、, 2015. Published January 2015. DOI: 10.1520/E2973-15.2For 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.Copyrig
17、ht ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1E2002 Practice for Determining Total Image Unsharpness inRadiologyE2446 Practice for Classification of Computed RadiologySystemsE2597 Practice for Manufacturing Characterization of Digi-tal Det
18、ector Arrays2.2 ASTM Adjuncts:2Digital Reference Images for Inspection of Aluminum andMagnesium Die Castings2.3 SMPTE Standard3RP133 SMPTE Recommended Practice Specifications forMedical Diagnostic Imaging Test Pattern for TelevisionMonitors and Hard-Copy Recording Cameras3. Terminology3.1 Definition
19、sDefinitions of terms used in this standardmay be found in Terminology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 aliasing, nartifacts that appear in an image when thespatial frequency of the input is higher than the output iscapable of reproducing. This will often appear as jagg
20、ed orstepped sections in a line or as moir patterns.3.2.2 contrast normalization, vthe adjustment of contrastbetween the production image and the reference image thatmakes the change in digital driving level versus change inthickness equal for both images.3.2.3 DDL, ndigital driving level, also know
21、n as monitorpixel value.3.2.4 discontinuity type, na specific discontinuity charac-terized by its cause and appearance. For example: shrinkage isa specific discontinuity type.3.2.5 discontinuity severity level, na relative rank in termsof “quantity, size, and distribution” of a collection of discon-
22、tinuities where “1” is the least and “4” is the greatest “quantity,size, and distribution” present on the reference image.3.2.6 graded illustrations, na category of discontinuitythat is assigned a severity level.3.2.7 measured resolution, nthe characteristic resolutionof a digital radiographic syste
23、m as measured in accordancewith 10.5.3.2.8 production image, nan image under review forcompliance with this standard.3.2.9 ungraded illustrations, na category of discontinuitywithout an assigned severity level.4. Appearance of Radiographic Indications4.1 The following descriptions are for use in dis
24、continuityidentification and classification. These descriptions apply tothese reference images only.4.1.1 Category A (Porosity)Round or elongated, smooth-edged spots of greater X-ray transmission occurring individu-ally distributed or in clusters.4.1.2 Category B (Cold Fill)A distinct line or band o
25、fvariable length and definite smooth outline, usually continuousor interconnected.4.1.3 Category C (Shrinkage)Filamentary or jagged areasof greater X-ray transmission, usually continuous or intercon-nected.4.1.4 Category D (Foreign Material)Isolated irregularvariation in film density, either lighter
26、 or darker than surround-ing areas. They may indicate the inclusion of oxide or dross ormetallic compounds of different density. Illustration shows amore dense material.5. Significance and Use5.1 Graded reference images are intended to provide a guideenabling recognition of specific casting disconti
27、nuity types andrelative severity levels that may be encountered during typicalmanufacturing processes. Reference images containing un-graded discontinuities are provided as a guide for recognitionof a specific casting discontinuity type where severity levelsare not needed. These reference images are
28、 intended as a basisfrom which manufacturers and purchasers may, by mutualagreement, select particular discontinuity classes to serve asstandards representing minimum levels of acceptability (seeSections 7 and 8). The reference images are intended to be usedfor casting thickness ranges in accordance
29、 with Table 1.5.2 Reference images represented by this standard may beused, as agreed upon in a purchaser supplier agreement, forenergy levels, thicknesses, or both outside the range of thisstandard when determined applicable for the casting serviceapplication.5.3 Procedures for evaluation of produc
30、tion images usingapplicable reference images of this standard are prescribed inSection 9; however, there may be manufacturing-purchaserissues involving specific casting service applications where itmay be appropriate to modify or alter such requirements.Where such modifications may be appropriate fo
31、r the castingapplication, all such changes shall be specifically called-out inthe purchaser supplier agreement or contractual document.3Available from the Society of Motion Picture and Television Engineers, 3Barker Avenue, White Plains, NY 10601, www.smpte.org/smpte_store.TABLE 1 Reference Radiograp
32、hs for Aluminum and MagnesiumDie CastingsDiscontinuity Plate Thickness,in. (mm)Applicable CastingThickness,in. (mm)Aluminum Die CastingsCategory A (Porosity)18 (3.2) Up to38 (9.5), incl.Category A (Porosity)58 (15.9) Over38 to1(9.5to25.4), incl.Category B (Cold Fill)18 (3.2) Up to38 (9.5), incl.Cate
33、gory C (Shrinkage)58 (15.9) Over38 to1(9.5to25.4), incl.Category D (ForeignMaterial)0.200 (5.08) Up to 1 (25.4), inclMagnesium Die CastingsCategory A (Porosity)18 (3.2) Up to38 (9.5), incl.Category A (Porosity)58 (15.9) Over38 to1(9.5to25.4), incl.Category B (Cold Fill)18 (3.2) Up to38 (9.5), incl.C
34、ategory C (Shrinkage)58 (15.9) Over38 to1(9.5to25.4), incl.Category D (ForeignMaterial)18 (3.2) Up to 1 (25.4), inclE2973 152Section 10 addresses purchaser supplier requisites for whereweld repairs may be required.5.4 Agreement should be reached between the cognizantengineering organization and the
35、supplier that the system usedby the supplier is capable of detecting and classifying therequired discontinuities.5.5 Image DeteriorationMany conditions can affect theappearance and functionality of digital reference images. Forexample, electrical interference, hardware incompatibilities,and corrupte
36、d files or drivers may affect their appearance. ThePractice E2002 line pair gauges located in the lower right handregion of each digital reference can be used as an aid to detectimage deterioration by comparing the measured resolutionusing the gauges to the resolution stated on the digital reference
37、image. Do not use the digital reference images if theirappearance has been adversely affected such that the interpre-tation and use of the images could be influenced.6. Basis of Application6.1 The digital reference images may be applied as accep-tance standards tailored to the end use of the product
38、. Appli-cation of these digital reference images as acceptance standardsshould be based on the intended use of the product and thefollowing considerations (see Note 3).6.1.1 Unless otherwise specified, discontinuities of equal orlesser severity than that in the specified reference radiographare acce
39、ptable in any specified unit area of the casting. The sizeof the unit area should be specified in the acceptance criteria.Discontinuities more severe than those in the specified refer-ence radiograph shall be considered rejectable.6.1.2 Any combination or subset of these digital referenceimages may
40、be used as is relevant to the particular application.Different grades or acceptance limits may be specified for eachdiscontinuity type. Furthermore, different grades may be speci-fied for different regions or zones of a component.6.1.3 Special considerations may be required where morethan one discon
41、tinuity type is present in the same area. Anymodifications to the acceptance criteria required on the basis ofmultiple discontinuity types must be specified.6.1.4 Where the reference image contains multiplediscontinuities, as in that case of gas holes or porosity,acceptance may be based upon the agg
42、regate area of thediscontinuities, the maximum discontinuity size in the refer-ence radiograph, the spacing between discontinuities, or acombination of these or other criteria, or both.6.1.5 As a minimum, the acceptance criteria should containinformation addressing: zoning of the part (if applicable
43、), theacceptance severity level for each discontinuity type, and thespecified area to which the digital reference images are to beapplied.NOTE 3Caution should be exercised in specifying the acceptancecriteria to be met in a casting. Casting design coupled with foundrypractice should be considered. I
44、t is advisable to consult with themanufacturer/foundry before establishing the acceptance criteria to ensurethe desired quality level can be achieved.7. Evaluation Procedure7.1 Select the appropriate digital reference image to matchthe condition to be evaluated in the production image.7.2 Apply cont
45、rast adjustments to the reference image usingthe method described in subsection 10.5.7.3 Evaluation shall be performed against the adjustedreference image.7.4 When the severity level of discontinuities in the produc-tion image being evaluated is equal to or less than the severitylevel in the specifi
46、ed reference image, that part of the castingrepresented by the production image shall be acceptable. If theproduction image shows discontinuities of greater severity thanthe reference image, that part of the casting shall be rejected.7.5 A unit area on the production image shall be evaluatedto a uni
47、t area of like size on the reference image. Any unitevaluation area that shares a discontinuity with an adjacent unitevaluation area shall meet the minimum unit area acceptabilityrequirements within the combined unit area. When the unitarea of interest of a production image is less than the unit are
48、aof the applicable reference image, such unit area of theproduction image shall be prorated to the reference image area.7.6 When two or more categories of discontinuity arepresent in the same production image, the predominatingdiscontinuities, if unacceptable, shall govern without regard tothe other
49、 categories of discontinuity and the casting rejected.7.7 When two or more categories of discontinuity arepresent to an extent equal to the maximum permissible level asshown in the applicable standards for each category, then thatpart of the casting shall be judged unacceptable. When two ormore categories of discontinuity are present in the same imageto an extent less than the maximum permissible level, as shownin the applicable standards for each category, the severity levelshall be evaluated by the overall aggregate condition. Theaggregate
