1、Designation: E 478 03Standard Test Methods forChemical Analysis of Copper Alloys1This standard is issued under the fixed designation E 478; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pare
2、ntheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 These test methods cover the chemical analysis ofcopper alloys havi
3、ng chemical compositions within the follow-ing limits:2Element Concentration, %Aluminum 12.0 maxAntimony 1.0 maxArsenic 1.0 maxCadmium 1.5 maxCobalt 1.0 maxCopper 40.0 minIron 6.0 maxLead 27.0 maxManganese 6.0 maxNickel 50.0 maxPhosphorus 1.0 maxSilicon 5.0 maxSulfur 0.1 maxTin 20.0 maxZinc 50.0 max
4、1.2 The test methods appear in the following order:SectionsAluminum by the Carbamate Extraction-(Ethyl-enedinitrilo) Tetraacetate Titrimetric TestMethod 2 to 12 % 70-77Copper by the Combined ElectrodepositionGravimetric and Oxalyldihydrazide Photomet-ric Test Method 50 %, minimum 9-17Iron by the 1,1
5、0-Phenanthroline PhotometricTest Method 0.003 to 1.25 % 18-27Lead by the Atomic Absorption Test Method0.002 to 15 % 89-99Lead by the (Ethylenedinitrilo)tetraacetic Acid(EDTA) Titrimetric Test Method 2.0 to30.0 % 28-35Nickel by the Dimethylglyoxime Extraction Pho-tometric Test Method 0.03 to 5.0 % 36
6、-45Nickel by the Dimethylglyoxime GravimetricTest Method 4 to 50 % 54-61Silver in Silver-Bearing Copper by the AtomicAbsorption Test Method 0.01 to 0.12 % 100-111Tin by the Iodatimetric Titration Test Method0.5 to 20 % 62-69Tin by the Phenylfluorone Photometric TestMethod 0.01 to 1.0 % 112-122Zinc b
7、y Atomic Spectrometry 0.2 to 2 % 78-88Zinc by the (Ethylenedinitrilo)tetraacetic Acid(EDTA) Titrimetric Test Method 2 to 40 % 46-531.3 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
8、sh appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with Specifications3E50 Practices for Apparatus, Reagents, and
9、Safety Precau-tions for Chemical Analysis of Metals4E60 Practice for Photometric and SpectrophotometricMethods for Chemical Analysis of Metals4E 173 Practice for Conducting Interlaboratory Studies ofMethods for Chemical Analysis of Metals4E 255 Practice for Sampling Copper and Copper Alloys forDeter
10、mination of Chemical Composition4E 1024 Guide for Chemical Analysis of Metals and MetalBearing Ores by Flame Atomic Absorption Spectropho-tometry4E 1601 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Analytical Method43. Significance and Use3.1 These test methods f
11、or the chemical analysis of metalsand alloys are primarily intended as referee methods to testsuch materials for compliance with compositional specifica-tions. It is assumed that all who use these methods will betrained analysts capable of performing common laboratoryprocedures skillfully and safely
12、. It is expected that work will beperformed in a properly equipped laboratory.4. Apparatus, Reagents, and Photometric Practice4.1 Apparatus and reagents required for each determinationare listed in separate sections preceding the procedure. The1These test methods are under the jurisdiction of ASTM C
13、ommittee E01 onAnalytical Chemistry for Metals, Ores and Related Materials and are the directresponsibility of Subcommittee E01.05 on Cu, Pb, Zn, Cd, Sn, Be, their Alloys andRelated Metals.Current edition approved Aug. 10, 2003. Published September 2003. Originallyapproved in 1973. Last previous edi
14、tion approved in 1996 as E 478 89a (1996).2The actual limits of application of each test method are presented in 1.2.3Annual Book of ASTM Standards, Vol 14.02.4Annual Book of ASTM Standards, Vol 03.05.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959
15、, United States.apparatus, standard solutions, and certain other reagents usedin more than one procedure are referred to by number and shallconform to the requirements prescribed in Practices E50,except that photometers shall conform to the requirementsprescribed in Practice E60.4.2 Photometric prac
16、tice prescribed in these test methodsshall conform to Practice E60.5. Hazards5.1 Specific hazard statements are given in Section 5, Note4, and Section 106.5.2 For other precautions to be observed in the use of certainreagents in these test methods, refer to Practices E50.6. Sampling6.1 For procedure
17、s for sampling the material, refer toPractice E 255. However, this method does not supersede anysampling requirements specified in a specific ASTM materialspecification.7. Rounding Calculated Values7.1 Calculated values shall be rounded to the desired num-ber of places as directed in Practice E29.8.
18、 Interlaboratory Studies8.1 These test methods were evaluated in accordance withPractice E 173 unless otherwise noted in the precision section.E 173 has been replaced by Practice E 1601. The Reproduc-ibility Index R2corresponds to the Reproducibility Index R ofPractice E 1601. Likewise the Repeatabi
19、lity Index R1of E 173corresponds to Repeatablility Index r of Practice E 1601.COPPER BY THE COMBINEDELECTRODEPOSITION GRAVIMETRIC ANDOXALYLDIHYDRAZIDE PHOTOMETRIC TESTMETHOD9. Scope9.1 This test method covers the determination of copper inconcentrations greater than 50 %.10. Summary of Test Method10
20、.1 After dissolution of the sample in nitric and hydrof-luoric acids, the oxides of nitrogen are reduced with hydrogenperoxide, and the copper deposited electrolytically. Loss ofplatinum from the anode is minimized by the addition of lead.The copper oxalyldihydrazide complex is formed with thecopper
21、 remaining in the electrolyte. Photometric measurementis made at approximately 540 nm.11. Interferences11.1 The elements ordinarily present do not interfere if theirconcentrations are under the maximum limits shown in 1.1.12. Apparatus12.1 Polytetrafluoroethylene or Polypropylene Beakers,250-mL capa
22、city.12.2 Polytetrafluoroethylene or Polypropylene Split Covers.12.3 Electrodes for ElectroanalysisPlatinum electrodes ofthe stationary type are recommended as described in 12.3.1 and12.3.2, but strict adherence to the exact size and shape of theelectrodes is not mandatory. When agitation of the ele
23、ctrolyteis permissible in order to decrease the time of deposition, oneof the types of rotating forms of electrodes, generally available,may be employed. The surface of the platinum electrodesshould be smooth, clean and bright to promote uniformdeposition and good adherence. Sandblasting is not reco
24、m-mended.12.3.1 CathodesPlatinum cathodes may be formed eitherfrom plain or perforated sheets or from wire gauze, and may beeither open or closed cylinders. Gauze cathodes are recom-mended, and shall be made preferably from 50-mesh gauzewoven from wire approximately 0.21 mm (0.0085 in.) indiameter.
25、The cathode should be stiffened by doubling thegauze for about 3 mm at the top and the bottom of the cylinderor by reinforcing the gauze at the top and bottom with aplatinum band or ring. The cylinder should be approximately30 mm in diameter and 50 mm in height. The stem should bemade from a platinu
26、m alloy wire such as platinum-iridium,platinum-rhodium, or platinum-ruthenium, having a diameterof approximately 1.30 mm. It should be flattened and weldedthe entire length of the gauze. The over-all height of thecathode should be approximately 130 mm. A cathode of thesedimensions will have a surfac
27、e area of 135 cm2exclusive of thestem.12.3.2 AnodesPlatinum anodes may be of the spiral typewhen anodic deposits are not being determined, or if thedeposits are small (as in the electrolytic determination of leadwhen it is present in amounts not over 0.2 %). When used inanalyses where both cathodic
28、and anodic plates are to bedetermined, the anodes should be of wire gauze. Spiral anodesshould be made from 1.00-mm or larger platinum wire formedinto a spiral of seven turns having a height of approximately 50mm and a diameter of 12 mm, the over-all height beingapproximately 130 mm. A spiral anode
29、of this description willhave a surface area of 9 cm2. Platinum gauze anodes should bemade of the same material and of the same general design asplatinum gauze cathodes. The anode cylinder should be ap-proximately 12 mm in diameter and 50 mm in height and theover-all height of the anode should be app
30、roximately 130 mm.A gauze anode of these dimensions will have a surface area of54 cm2. Both areas are exclusive of the stem.12.3.3 Gauze cathodes are recommended where rapid elec-trolysis is used.13. Reagents13.1 Ammonium Chloride Solution (0.02 g/L)Dissolve0.02 g of ammonium chloride (NH4Cl) in wat
31、er and dilute to 1L.13.2 Hydrogen Peroxide (3 %)Dilute 100 mL of 30 %hydrogen peroxide to 1 L.13.3 Lead Nitrate Solution (10 g/L)Dissolve 10.0 g oflead nitrate (Pb(NO3)2) in water and dilute to 1 L.14. Procedure14.1 Transfer a 2.000-g sample, weighed to the nearest 0.1mg, to a 250-mL poly(tetrafluor
32、oethylene) or polypropyleneE478032beaker, add 2 mL of HF, and 30 mL of HNO3(1 + 1). Coverwith a cover glass and allow to stand for a few minutes until thereaction has nearly ceased. Warm but do not heat over 80C.When dissolution is complete, add 25 mL of 3 % H2O2and 3mL of Pb(NO3)2solution. Rinse th
33、e cover glass and dilute toapproximately 150 mL with NH4Cl solution.14.2 With the electrolyzing current off, position the anodeand the accurately weighed cathode in the solution so that thegauze is completely immersed. Cover the beaker with a splitplastic cover.14.3 Start the electrolysis and increa
34、se the voltage until theammeter indicates a current which is equivalent to about 1.0A/dm2and electrolyze overnight. Alternatively electrolyze at acurrent density of 4A/dm2for 1.5 h. (The more rapid procedurerequires the use of gauze electrodes).14.4 Slowly withdraw the electrodes (or lower the beake
35、r)with the current still flowing, and rinse with a stream of waterfrom a wash bottle. Quickly remove the cathode, rinse it inwater, and then dip into two successive baths of ethanol ormethanol. Dry in an oven at 110C for 3 to 5 min.14.5 Return the voltage to zero, and turn off the switch.Reserve the
36、 electrolyte.14.6 Allow the electrode to cool to room temperature, andweigh.15. Calculation15.1 Calculate the percentage of copper as follows:Copper, % 5 A 1 B/C 3 100 (1)where:A = deposited copper, g,B = copper in the electrolyte as calculated in 16.10,g,andC = sample used, g.16. Photometric Determ
37、ination of the Residual Copper inthe Electrolyte16.1 InterferencesThe elements ordinarily present do notinterfere if their concentrations are under the maximum limitsshown in 1.1.16.2 Concentration RangeThe recommended concentra-tion range is from 0.0025 to 0.07 mg of copper per 50 mL ofsolution, us
38、ing a 2-cm cell.NOTE 1This procedure has been written for cells having a 2-cm lightpath. Cells having other dimensions may be used, provided suitableadjustments can be made in the amounts of sample and reagents used.16.3 Stability of ColorThe color fully develops in 20 min,and is stable for 1 h.16.4
39、 Reagents:16.4.1 Acetaldehyde Solution (40 %)Dilute 400 mL ofacetaldehyde to 1 L with water.16.4.2 Boric Acid Solution (50 g/L)Dissolve 50 g of boricacid (H3BO3) in hot water, cool, and dilute to 1 L.16.4.3 Citric Acid Solution (200 g/L)Dissolve 200 g ofcitric acid in water and dilute to 1 L.16.4.4
40、Copper, Standard Solution A (1 mL = 1.0 mg Cu)Transfer a 1.000-g sample of electrolytic copper (purity:99.9 % minimum) to a 250-mLbeaker and add 10 mLof HNO3(1 + 1). Evaporate till nearly to dryness. Add 5 mL of water todissolve the residue. Transfer to a 1-L volumetric flask, diluteto volume, and m
41、ix.16.4.5 Copper, Standard Solution B (1 mL = 0.010 mgCu)Using a pipet, transfer 10 mL of copper solution A (1mL = 1.0 mg Cu) to a 1-L volumetric flask, dilute to volumeand mix.16.4.6 Oxalyldihydrazide Solution (2.5 g/L)Dissolve 2.5g of oxalyldihydrazide in warm water and dilute to 1 L.16.5 Preparat
42、ion of Calibration Curve:16.5.1 Calibration Solutions:16.5.1.1 Transfer 25 mL of boric acid solution to a 250-mLvolumetric flask and then add a solution containing 150 mL ofwater, 2 mL of HF, and 30 mL of HNO3(1 + 1). Dilute tovolume, and mix.16.5.1.2 Transfer 10 mL of this solution to each of four5
43、0-mL volumetric flasks. Using pipets, transfer 1, 3, 5, and 7mL of copper solution B (1 mL = 0.010 mg Cu) to the flasks.Proceed as directed in 16.5.3.16.5.2 Reference SolutionAdd 10 mL of boric acid solu-tion prepared as directed in 16.5.1.1 to a 50-mL volumetricflask and proceed as directed in 16.5
44、.3.16.5.3 Color DevelopmentAdd in order, and with mixingafter each addition, 5 mL of citric acid solution, 6 mL ofNH4OH, 10 mL of acetaldehyde solution, and 10 mL ofoxalyldihydrazide solution. Cool, dilute to volume, and mix.Allow to stand for 30 min and proceed as directed in 16.5.4.16.5.4 Photomet
45、ry:16.5.4.1 Multiple-Cell PhotometerMeasure the cell cor-rection using absorption cells with a 2-cm light path and a lightband centered at approximately 540 nm. Using the test cell,take the photometric readings of the calibration solutions.16.5.4.2 Single-Cell PhotometerTransfer a suitable por-tion
46、of the reference solution to an absorption cell with a 2-cmlight path and adjust the photometer to the initial setting usinga light band centered at approximately 540 nm. While main-taining this adjustment, take the photometric readings of thecalibration solutions.16.5.5 Calibration CurvePlot the ne
47、t photometric-readings of the calibration solutions against milligrams ofcopper per 50 mL of solution.16.6 Test SolutionTransfer the reserved electrolyte to a250-mL volumetric flask containing 25 mL of boric acidsolution, dilute to volume, and mix. Using a pipet, transfer 10mL to a 50-mL volumetric
48、flask (Note 2). Proceed as directedin 16.8.NOTE 2If the solution shows a permanganate color, add sodiumnitrite solution (20 g/L) dropwise until the color is discharged, and thenproceed as directed in 16.8.16.7 Reference SolutionProceed as directed in 16.5.2.16.8 Color DevelopmentProceed as directed
49、in 16.5.3.16.9 PhotometryTake the photometric reading of the testsolution as directed in 16.5.4.16.10 CalculationConvert the net photometric reading ofthe test solution to milligrams of copper by means of thecalibration curve. Calculate the grams of copper in the totalelectrolyte as follows:E478033Copper, g 5 A 3 25!/1000 (2)where:A = copper found in 50 mL of the final test solution, mg.17. Precision and Bias17.1 PrecisionEight laboratories cooperated in testingthis test method and obtained the data summarized in Table 1.17.2 Bi
copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1