1、Designation: F2895 15Standard Practice forDigital Radiography of Cast Metallic Implants1This standard is issued under the fixed designation F2895; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number
2、in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice covers the procedure for digital radio-graphic testing of cast metallic surgical implants and relatedweldments.1.2 Digital X-ra
3、y is an alternative method for radiographyof cast metallic surgical implants and related weldments (seePractice F629).1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsy
4、stem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith 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 establi
5、sh appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3E94 Guide for Radiographic ExaminationE192 Reference Radiographs of Investment Steel Castingsfor Aerospace ApplicationsE746 Practice for Dete
6、rmining Relative Image Quality Re-sponse of Industrial Radiographic Imaging SystemsE1030 Test Method for Radiographic Examination of Me-tallic CastingsE1316 Terminology for Nondestructive ExaminationsE1742 Practice for Radiographic ExaminationE2007 Guide for Computed RadiographyE2033 Practice for Co
7、mputed Radiology (PhotostimulableLuminescence Method)E2660 Digital Reference Images for Investment Steel Cast-ings for Aerospace ApplicationsE2669 Digital Reference Images for Titanium CastingsF629 Practice for Radiography of Cast Metallic SurgicalImplants2.2 ASNT Standard:ASNTTC1A Personnel Qualifi
8、cation and Certification inNondestructive Testing43. Terminology3.1 DefinitionsFor additional terminology, consult Termi-nology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 contrast, ndifference in gray scale level between anarea and its immediate surroundings as presented on the f
9、inaldigital radiographic image.3.2.2 digital image, nimage composed of discrete pixelsof digital brightness values.3.2.3 digital image contrast, nrange of gray scale valuesin an image in which a high contrast indicates that the imagecontains largely black-and-white brightness values with a widerange
10、 of gray shades.3.2.4 electronic imaging, vmeans of converting the imagestored on the imaging plate or detector into a standard videooutput format.3.2.5 electronic imaging system, nsystem that takes datafrom a storage imaging plate or detector and converts it into astandard analog or digital electro
11、nic signal.3.2.6 filters, nsheets of copper or other material placed inthe radiation beam either at the X-ray tube or between thespecimen and the detector to improve the quality by selectivelyremoving low-energy radiation from the radiation beam andabsorbing scattered radiation.3.2.7 gray scale, nnu
12、meric values representing displaybrightness.3.2.8 gray scale range, nrange of numeric values repre-senting the brightest and darkest portion of the image display.3.2.9 image display parameters, nall variables necessaryto standardize the video image.1This practice is under the jurisdiction ofASTM Com
13、mittee F04 on Medical andSurgical Materials and Devices and is the direct responsibility of SubcommitteeF04.12 on Metallurgical Materials.Current edition approved May 15, 2015. Published June 2015. Originallyapproved in 2010. Last previous edition approved in 2010 as F2895 10. DOI:10.1520/F2895-15.3
14、For 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.4Available from the American Society for Nondestructive Testin
15、g, Inc., PO Box28518, Columbus, OH 43228-0518, http:/www.asnt.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.9.1 DiscussionThese include, but are not limited to
16、,brightness, contrast, and linearity.3.2.10 image processing, velectronic enhancement of theraw image signal to improve fine-detail detectability in the testobject and achieve required sensitivity.3.2.10.1 DiscussionThese include, but are not limited to,techniques such as noise reduction, contrast e
17、nhancement, andspatial filtering.3.2.11 image quality level, nability of the inspectionsystem to demonstrate a specific relative image quality indica-tor (RIQI) sensitivity.3.2.12 imaging plate, IP, nradiation sensitive detector thatis capable of detecting and storing input signal information thatca
18、n subsequently be converted into a corresponding opticalsignal.3.2.13 IP reader, ndevice capable of retrieving storedinformation from the imaging plate and converting this infor-mation into digital data for subsequent viewing on a videomonitor.3.2.14 masking, nlead or other high-density materialplac
19、ed on or around a test object during exposure for thepurpose of minimizing the effect of secondary or scatteredradiation.3.2.15 material thickness, nshall be the nominal thicknessor actual thickness if measured at the area being radiographed.3.2.16 National Institute of Standards and Technology,NIST
20、, nfederal technology agency that develops and pro-motes measurements, standards, and technology.3.2.17 nondestructive inspection (NDI) procedure,nwritten set of instructions that identify equipmentstandardization, parameters, and setup for conducting a non-destructive test or inspection.3.2.17.1 Di
21、scussionThe procedure may be broken into thefollowing two parts: a general procedure that has the basicinstructions on performing an inspection and a technique sheetthat has the detailed instructions for specific parts.3.2.18 penetrameter, nstrip of material of the same orsimilar composition as that
22、 of the material being examinedrepresenting a percentage of section thickness and providedwith a combination of steps, holes, or quality levels.3.2.18.1 DiscussionWhen placed in the path of radiation,the resultant radiographic image demonstrates the quality ofthe radiographic technique. It is also k
23、nown as an imagequality indicator (IQI). It is not intended for use in judging thesize or for establishing acceptance limits of discontinuities.3.2.19 penetrameter sensitivity, nindication of the abilityof the radiographic process to show: (1) the difference inmaterial thickness by exhibiting a diff
24、erence of radiographiccontrast and (2) detail definition by the resolution of holes of aspecific size.3.2.20 pixel, nsmallest unit of storage in a digital imagethat can be discretely controlled by the display system.3.2.20.1 DiscussionA pixel is described by its horizontaland vertical location withi
25、n a digital matrix.3.2.21 pixel intensity value, PV, nsee Practice E746 fordescription and discussion.3.2.22 quality level 2, nquality level designation in whichthe 2T hole is visible in a 2 % penetrameter; previously knownas 22T sensitivity.3.2.23 radiation source, nmachine or radioisotope thatemit
26、s penetrating radiation.3.2.24 radiographic image, nvisible image produced bythe penetration of radiation through the material being tested.3.2.25 radiographic inspection, nuse of penetrating radia-tion source to detect discontinuities in material by presentingtheir images on a recording medium suit
27、able for interpretationby qualified personnel.3.2.26 radiographic quality level, nability of a radio-graphic procedure to demonstrate a certain penetrameter sen-sitivity.3.2.27 recording media, nrecording media and storageformat for mandatory radiographic image storage.3.2.28 recording medium, ndete
28、ctor that converts radia-tion into a visible image or a signal that can be transformed intoa visible image at a later date.3.2.28.1 DiscussionAlso known as an imaging plate.3.2.29 relative image quality indicator, RIQI, nimagequality measuring device that is capable of determining mean-ingful differ
29、ences between two or more radiographic imagingsystems or changes of individual components of radiographicimaging systems.3.2.30 sensitivity, ngeneral or qualitative term referring tothe size of the smallest detail that can be seen on the imagingdisplay or recording medium or both or the ease with wh
30、ichdetails can be seen.3.2.31 technique, ncategory within a method, forexample, digital radiographic testing or fluorescent penetrantinspection.3.2.32 technique card, ndetailed, written instructions(may be in the form of a sheet, card, or other documentation)that supplement the instructions of a gen
31、eral procedure.3.2.33 test object, nmaterial, component, or assembly thatis the subject of the radiographic examination.3.2.34 X-ray control number, ninspection serial numbersor code letters used to provide traceability.4. Significance and Use4.1 The requirements expressed in this practice are inten
32、dedto control the quality of the digital radiographic image of castmetallic surgical implants.5. Radiographic Methods5.1 The radiographic method shall be agreed upon betweenthe purchaser and supplier but should be in accordance withTest Method E1030, Guides E94 and E2007, and PracticeE2033.5.2 Frequ
33、ency and CoverageThe number of componentsinspected (frequency) and the coverage of each componentshall be mutually agreed upon between the supplier and theF2895 152customer. If the amount of inspection is not specified, allcastings requiring radiographic inspection shall receive 100 %radiographic co
34、verage. The orientation of the radiation beamand the number of exposures for any casting shall be governedby the test object geometry, the probable size and location ofthe various types of discontinuities to be detected, and therequirements of the applicable specifications and drawings.5.3 Image Qua
35、lity Indicators (IQIs)IQIs shall preferen-tially be from material of the same composition or radiographi-cally similar material as the object to be radiographed, exceptthat IQIs of less dense material may be used in lieu ofhigh-density penetrameters (that is, stainless steel in place ofnickel). Unde
36、rsized IQIs may be used in lieu of properthickness size.5.4 IQIs and blocks shall be used and procured in accor-dance with Practice E1742. The supplier shall certify compli-ance with respect to alloys and dimensions.5.4.1 In some cases components created from alloys thathave a high degree of grain d
37、iffraction may in certain sizeranges be difficult to image the 2T on cast IQI blocks. In thatsituation the radiographic system shall be validated usingspecimens that contain a known discontinuity.5.5 Energies between 250 and 400 kV may be required toradiograph surgical implants with a 12.7 mm 12 in.
38、 or greatermaterial thickness.5.6 Computed Radiography (CR)Uses very similar equip-ment to conventional radiography except that in place of a filmto create the image, an imaging plate (IP) made of photostimu-lable phosphor is used. The imaging plate housed in a specialcassette and placed under the b
39、ody part or object to beexamined and the X-ray exposure is made. The imaging plateis then run through a special laser scanner, or CR reader, thatreads and digitizes the image. The digital image can then beviewed and enhanced using software that has functions verysimilar to other conventional digital
40、 image-processingsoftware, such as contrast, brightness, filtration and zoom.5.7 Digital Radiography (DR) or (DX)Referred to asfilmless X-ray image capturing. In place of X-ray film, a digitalimage capture device is used to record the X-ray image andmake it available as a digital file that can be pr
41、esented forinterpretation and saved as part of a permanent record. DRallows the user to immediately preview the image. A widerdynamic range makes it more forgiving for over- and under-exposure; as well as the ability to apply special imageprocessing techniques that enhance overall display of theimag
42、e.5.8 When required a gage repeatability and reproducibilitystudy may be required on personnel and equipment. The resultsof the study must show equivalence between the film imageand the digital image.6. Sensitivity Requirements6.1 Unless otherwise specified, the required image qualitylevel shall be
43、2, previously known as 22T sensitivity perPractice E1742. This shall be demonstrated by the ability of theradiographer to discern the 2T hole on the required penetram-eters.6.2 IQI Coverage and Area of InterestIQIs shall beincluded in all radiographic images for product acceptance.Each IQI shall rep
44、resent an area of interest in which radio-graphic pixel values are within 15 % of the pixel valuemeasured through the body of the IQI.6.3 Penetrameter material selection shall be based on Prac-tice E1742.7. Metallurgical Requirements7.1 The product acceptance and rejection criteria shall be asagreed
45、 upon between the purchaser and supplier.7.2 The mutually agreed upon acceptance or rejection limitsshall use ASTM reference radiographs E192 or digital refer-ence images E2660 or E2669.8. Personnel Certification8.1 The personnel performing radiography under this prac-tice shall be certified in acco
46、rdance with ASNTTC1A or arecognized national equivalent.8.2 The personnel performing radiographic interpretationshall be certified Level II or Level III individuals, orequivalent, in accordance with ASNTTC1A or a recognizednational equivalent.9. Report and Storage9.1 A certified report shall be main
47、tained showing radio-graphic test results including any rejected pieces. The reportcontent when required shall be agreed between purchaser andsupplier.9.2 The archived radiographic image may be reproduced,rerecorded, or transferred to another storage media providedthe quality level of the reproducti
48、on is the same image qualityas that used to disposition the casting initially.9.3 Storage of digital images shall be in a format as agreedupon between the purchaser and supplier.9.4 Reports and radiographs, or an equivalent digital imageof a radiograph, shall be maintained by the purchaser, or asagr
49、eed upon between purchaser and supplier.10. Keywords10.1 cast metallic surgical devices; cast metallic surgicalimplants and weldments; computed radiography; digital image;digital radiography; digital x-ray; electronic imaging; implants;NDT; NDTE; nondestructive testingF2895 153APPENDIX(Nonmandatory Information)X1. RATIONALEX1.1 The acceptance criteria for the digital radiographicexamination of cast metallic surgical implants and relatedweldments are based on reference radiographs presented inReference Radiographs E192, or
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