1、Designation: E 1476 04Standard Guide forMetals Identification, Grade Verification, and Sorting1This standard is issued under the fixed designation E 1476; 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.1. Scope1.1 This guide is intended for tutorial purposes only. Itdescribes the general requirements, methods, and proceduresfor the nondestructiv
3、e identification and sorting of metals.1.2 It provides guidelines for the selection and use ofmethods suited to the requirements of particular metals sortingor identification problems.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is ther
4、esponsibility 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. For specificprecautionary statements, see Section 10.2. Referenced Documents2.1 ASTM Standards:2E 158 Practice for Fundamental Cal
5、culations to ConvertIntensities into Concentrations in Optical Emission Spec-trochemical AnalysisE 305 Practices for Establishing and Controlling Spectro-chemical Analytical CurvesE 322 Method for X-Ray Emission Spectrometric Analysisof Low-Alloy Steels and Cast IronsE 566 Practice for Electromagnet
6、ic (Eddy-Current) Sortingof Ferrous MetalsE 572 Test Method for X-Ray Emission SpectrometricAnalysis of Stainless SteelE 703 Practice for Electromagnetic (Eddy Current) Sortingof Nonferrous MetalsE 977 Practice for Thermoelectric Sorting of ElectricallyConductive MaterialsF 355 Test Method for Shock
7、 Absorbing Properties ofPlaying Surface Systems and MaterialsF 1156 Terminology Relating to Product Counterfeit Pro-tection Systems3. Terminology3.1 DefinitionsTerms used in this guide are defined in thestandards cited in Section 2 and in current technical literatureor dictionaries; however, because
8、 a number of terms that areused generally in nondestructive testing have meanings orcarry implications unique to metal sorting, they appear withexplanation in Appendix X1.4. Significance and Use4.1 A major concern of metals producers, warehouses, andusers is to establish and maintain the identity of
9、 metals frommelting to their final application. This involves the use ofstandard quality assurance practices and procedures throughoutthe various stages of manufacturing and processing, at ware-houses and materials receiving, and during fabrication and finalinstallation of the product. These practic
10、es typically involvestandard chemical analyses and physical tests to meet productacceptance standards, which are slow. Several pieces from aproduction run are usually destroyed or rendered unusablethrough mechanical and chemical testing, and the results areused to assess the entire lot using statist
11、ical methods. Statisticalquality assurance methods are usually effective; however,mixed grades, off-chemistry, and nonstandard physical proper-ties remain the primary causes for claims in the metalsindustry. A more comprehensive verification of product prop-erties is necessary. Nondestructive means
12、are available tosupplement conventional metals grade verification techniques,and to monitor chemical and physical properties at selectedproduction stages, in order to assist in maintaining the identi-ties of metals and their consistency in mechanical properties.4.2 Nondestructive methods have the po
13、tential for monitor-ing grade during production on a continuous or statistical basis,for monitoring properties such as hardness and case depth, andfor verifying the effectiveness of heat treatment, cold-working,and the like. They are quite often used in the field for solvingproblems involving off-gr
14、ade and mixed-grade materials.4.3 The nondestructive methods covered in this guide pro-vide both direct and indirect responses to the sample beingevaluated. Spectrometric analysis instruments respond to thepresence and percents of alloying constituents. The electro-magnetic (eddy current) and thermo
15、electric methods, on theother hand, are among those that respond to properties in thesample that are affected by chemistry and processing, and they1This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-tive Testing and is the direct responsibility of Subcommittee E07.10 on Emergin
16、gNDT Methods.Current edition approved March 1, 2004. Published April 2004. Originallyapproved in 1992. Last previous edition approved in 1997 as E 1476 - 97.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of AS
17、TMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.yield indirect information on composition and mechanicalproperties. In this guide, the sp
18、ectrometric methods are classi-fied as quantitative, whereas the methods that yield indirectreadings are termed qualitative.4.4 This guide describes a variety of qualitative and quan-titative methods. It summarizes the operating principles of eachmethod, provides guidance on where and how each may b
19、eapplied, gives (when applicable) the precision and bias thatmay be expected, and assists the investigator in selecting thebest candidates for specific grade verification or sorting prob-lems.4.5 For the purposes of this guide, the term “nondestruc-tive” includes techniques that may require the remo
20、val of smallamounts of metal during the examination, without affecting theserviceability of the product.4.6 The nondestructive methods covered in this guide pro-vide quantitative and qualitative information on metals prop-erties; they are listed as follows:4.6.1 Quantitative:4.6.1.1 X-ray fluorescen
21、ce spectrometry, and4.6.1.2 Optical emission spectrometry.4.6.2 Qualitative:4.6.2.1 Electromagnetic (eddy current),4.6.2.2 Conductivity/resistivity,4.6.2.3 Thermoelectric,4.6.2.4 Chemical spot tests,4.6.2.5 Triboelectric, and4.6.2.6 Spark testing (special case).5. Background5.1 The standard quality
22、assurance procedures for verifyingthe composition and physical properties of a metal at aproducing facility are through chemical analysis and mechani-cal testing. These required tests result in the sacrifice of acertain amount of production for the preparation of samples,are costly and time-consumin
23、g, and may not provide timelyinformation regarding changes in product quality. In a marketin which a single failure can result in heavy litigation anddamage costs, the manufacturer requires assurance that hisproduction will meet the customers acceptance standards.Nondestructive grade verification pr
24、ovides one means of moni-toring production to ensure that the product will meet accep-tance requirements.5.2 Nondestructive methods may be used in conjunctionwith the accepted standard product quality tests to providecontinuous verification that current production lies within theagreed upon acceptan
25、ce limits specified. In-line electromag-netic examinations may be used to indicate the consistency ofproduction. Any deviation from the norms set for the accep-tance band will result in automatic alarms, kick-out, or othermeans of alerting production personnel of a problem. Thusalerted, the mill can
26、 determine the cause for the alarm and takecorrective action. Portable optical emission spectrometry unitsmay be used to determine the concentrations of criticalelements without having to resort to slow physical and chemi-cal analyses. A quality assurance program combining conven-tional measurements
27、 with suitable nondestructive methods canprovide effective and timely information on product composi-tion and physical properties. This will result in improvedquality and yield; savings in time, labor, and material; andreduced field failures and claims. This guide provides specificinformation regard
28、ing nondestructive metals identification,grade verification, and sorting methods to assist in selecting theoptimum approach to solving specific needs.5.3 Spectrometric methods are capable of directly indicatingthe presence and percent of many of the elements thatcharacterize a metal grade. The spect
29、rometric and thermoelec-tric techniques examine only the outermost surfaces of thesample or material. As a result, for grade verification purposes,it may be necessary to grind sufficiently deep to ensure accessto the base metal for accurate readings. However, grinding mayaffect the thermoelectric re
30、sponse. The spectrometric methodsrequire physical contact and often some surface preparation.The electromagnetic method, however, does not require con-tact and very often is suited for on-line, automatic operation.The thermoelectric method, although requiring contact, re-sponds to many of the same p
31、arameters that influence theelectromagnetic responses. Both respond to chemical compo-sition, processing, and treatments that affect the physical andmechanical properties of the product. Nondestructive methodsfor indicating the mechanical properties of a metal are beyondthe scope of this guide.5.4 E
32、ach method has particular advantages and disadvan-tages. The selection of suitable candidates for a specific gradeverification or sorting application requires an understanding ofthe technical operating features of each method. These includethe precision and bias necessary for the application andprac
33、tical considerations such as product configuration, surfacecondition, product and ambient temperatures, environmentalconstraints, etc.6. General Procedures6.1 Standardization/Calibration:6.1.1 Of primary concern in any materials identification orsorting program is delineation of the pertinent produc
34、t charac-teristics (such as chemical composition, processing, configu-ration, and physical properties) and the assignment of accep-tance limits to each. Often prescribed by materialsspecifications, they also may result from quality assuranceprocedures or by agreement between the producer and the use
35、r.6.1.2 Of equal importance is the selection of referencestandards. Quantitative methods employ coupon standards thatare representative of the metals or alloy compositions to beverified, and the analytical instrumentation is standardizedagainst them. The indirect methods, particularly those thatresp
36、ond to physical properties as well as composition, requirereference standards that will represent the material specified incomposition, mechanical and physical properties, and process-ing, as well as cover the means and extremes of the acceptanceband. Coupon reference standards or product reference
37、stan-dards, or both, may be selected as required.6.1.2.1 Coupon Reference StandardsThese are small, eas-ily handled metal panels made to specified chemical composi-tions. They are available commercially in sets, singly, or tospecification. They are useful for instrument standardization,determining s
38、eparability among metals, and field use withE1476042portable equipment. They are not intended to reflect the effectsof processing or heat treatment on the acceptability of aproduct.6.1.2.2 Product Reference StandardsThese must repre-sent the product specified in composition and mechanical andphysica
39、l properties. Ideally, three or more product referencestandards covering the mean, plus two or more covering theextremes, should be obtained, suitably catalogued, and markedfor proper identification.6.1.3 Standardization or calibration procedures, or both, foreach method must be followed as specifie
40、d by the instrumentmanufacturer. Coupon reference standards are used to stan-dardize and set up quantitative (spectrometric) or qualitative(thermoelectric and chemical spot test, etc.) verifications, aswell as for metals sorting checks on electromagnetic, electricalconductivity, and similar instrume
41、nts. Rod, bar, wire, andtubular product reference standards are used almost exclusivelyfor the qualitative methods, such as the electromagnetic,electrical conductivity, triboelectric, and spark tests. These arefabricated from the product being manufactured, from sampleswith compositions and physical
42、 properties verified throughanalytical examinations.6.1.4 The known product reference standards used for thequalitative methods must be representative of the chemistry,processing, surface, and other physical and mechanical param-eters that might affect readings. Product standard parametersmust be ve
43、rifiable.6.1.5 Coupon reference standards are useful for initialinstrument adjustments, but final adjustments should be madeon standard samples verified as representative of good produc-tion pieces.6.1.6 Product standard samples will disclose potential errorsthat might result from surface alloy depl
44、etion, heavy oxidelayers, or hardness variations resulting from processing anoma-lies. Such known variables must be used to determine finalacceptance limits for any examination, and they will aidmaterially in both selecting a method and optimizing theexamination conditions.6.2 Test Piece Requirement
45、s:6.2.1 The relationship between the standard productsamples and pieces being evaluated must be understoodclearly. This is of particular importance when using theelectromagnetic method. Composition, size, processing, sur-face condition, finish, straightness, and temperature must benominally the same
46、 as that represented by the standardsamples. To a lesser degree, this is also true for the thermo-electric method. For the other methods, size, configuration, andmechanical processing usually do not affect composition read-ings to any significant degree.6.2.2 The means for performing the examination
47、 must becontrolled. If some surface metal removal is necessary (as it isfor spectrometric examinations), the amount of removal, meansof removal, and removal location on the piece must bespecified and monitored closely. For electromagnetic examina-tions, the piece should be positioned in the same man
48、nerrelative to the coil as is the product standard sample. Failure tocontrol variables can result in the misidentification of samples.6.3 Display and Accept/Reject Criteria:6.3.1 Most systems employ some form of visual display orreadout to indicate the response to piece variables. Meterreadings, osc
49、illoscope patterns, digital signals, and coloredspots (from a reagent in chemical spot testing) are typicalexamples. On instruments with digital or cathode ray tubedisplays, it is common practice to show the position and extentof adjustable gates for the setting of automatic alarm circuits.6.3.2 Automatic alarm gates may be positioned and adjustedto be triggered by the presence or absence of a signal of a givenamplitude and location. Both of these are adjustable. They aredesigned for use in automatic or operator-assisted systems toindicate when a product falls outside the acceptance
