1、Designation: C 715 90 (Reapproved 2006)Standard Test Method forNickel on Steel for Porcelain Enameling by PhotometricAnalysis1This standard is issued under the fixed designation C 715; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, the year of last revision. A 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 test method covers the determination of the amountof nickel deposited on sheet steel during its pr
3、eparation forporcelain enameling. It is a photometric method commonlyused on production parts and is suitable for determining theheavier nickel deposits that may be obtained during theprocessing of steel for one-coat enameling.NOTE 1An alternative X-ray emission spectrometry method is TestMethod C 8
4、10.1.2 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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Reference
5、d Documents2.1 ASTM Standards:2C 810 Test Method for Nickel on Steel for Porcelain Enam-eling by X-Ray Emission SpectrometryE30 Test Methods for Chemical Analysis of Steel, CastIron, Open-Hearth Iron, and Wrought Iron3E60 Practice for Analysis of Metals, Ores, and RelatedMaterials by Molecular Absor
6、ption Spectrometry3. Significance and Use3.1 This test method is primarily used to control the nickeldipping operation to ensure that the desired level of nickeldeposition is attained. It is also used to prepare test plates usedfor calibration in Test Method C 810.4. Apparatus4.1 Photoelectric Photo
7、meter, conforming to Practice E60.4.2 Weighted Rubber Ring Assembly, required to confinestripping agents to a definite area, consisting of a moldedrubber ring and a metal outer ring. The rubber ring shall havean inside diameter of 1.35 in. (34.3 mm) in order to encircle anarea of 0.01 ft2(0.000929 m
8、2), a wall configuration as shownin Fig. 1, and the lower portion beveled at a 45 angle (0.78rad) to reduce the contact area and ensure a better seal. Themetal outer ring shall weigh about 3.5 lb (1.5 kg), suitablymachined to fit over the top of the rubber ring as shown in Fig.1.4.2.1 The exact area
9、 covered by the rubber ring willgradually increase as the rubber ring itself is consumed by theacid reagent used. In the most accurate analysis, the area etchedby the rubber ring shall be calculated occasionally, factoredagainst the prescribed area, and that number applied to thereading obtained fro
10、m the graph.4.3 Aspirator, consisting of a calibrated 500-mL flask,equipped with a twohole stopper, an aspirator bulb, and asuction tube formed from 0.079-in. (2-mm) inside diametercapillary glass tubing.5. Reagents and Materials5.1 Reagent grade chemicals shall be used in all tests.Unless otherwise
11、 indicated, it is intended that all reagents shallconform to the specifications of the Committee of AnalyticalReagents of the American Chemical Society.4Other gradesmay be used, provided it is first ascertained that the reagent isof sufficiently high purity to permit its use without lesseningthe acc
12、uracy of the determination.5.2 Purity of WaterUse distilled or deionized water.5.3 Ammonium Hydroxide (sp gr 0.90)Concentrated am-monium hydroxide (NH4OH).5.4 Ammonium Persulfate(NH4)2S2O8.5.5 DimethylglyoximePrepare a 1 % solution of dimeth-ylglyoxime in methyl alcohol or a 2.62 % solution of sodiu
13、mdimethylglyoximate in water (store in a polyethylene bottle).1This test method is under the jurisdiction ofASTM Committee B08 on Metallicand Inorganic Coatings and is the direct responsibility of Subcommittee B08.12 onMaterials for Porcelain Enamel and Ceramic-Metal Systems.Current edition approved
14、 April 1, 2006. Published April 2006. Originallyapproved in 1977. Last previous edition approved in 2000 as C 715 90 (2000).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, r
15、efer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for Laboratory
16、Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.6 Hydrochloric Acid (1+5)D
17、ilute 1 vol of concentratedhydrochloric acid (HCl, sp gr 1.19) with 5 vol of water.5.7 Nickel Sulfate, Standard Solution Dissolve 0.448 g ofnickel sulfate (NiSO46H2O) in water. When the material iscompletely dissolved, cautiously add 10 mL of concentratedH2SO4and transfer the solution to the 1000-mL
18、 flask. Whencool, make up to the mark with water. One millilitre of thisstandard solution is equivalent to 0.0001 g of nickel permillilitre.5.8 Nitric Acid (1+1)Dilute 1 vol of concentrated nitricacid (HNO3, sp gr 1.42) with 1 vol of water.5.9 Sulfuric Acid (sp gr 1.84)Concentrated sulfuric acid(H2S
19、O4).6. Sampling6.1 Sampling frequency shall be consistent with the objec-tive of control of the nickel dipping operation.7. Standardization of Photoelectric Photometer7.1 The photoelectric photometer shall be standardized asfollows:7.1.1 Using a buret, accurately measure out 2, 4, 8, 12, 16,and 20 m
20、L portions of nickel sulfate standard solution. Theseamounts are equivalent to 0.2, 0.4, 0.9, 1.3, 1.7, and 2.1 g ofnickel per square metre (0.02, 0.04, 0.08, 0.12, 0.16, and 0.20g of nickel per square foot) of surface when specimens fromthe steel surface are obtained as prescribed. (Iron in solutio
21、nthat is dissolved from the steel surfaces has a negligible effecton the nickel determinations.) Using the standard analyticalprocedures described in 8.2, determine the percent transmis-sion at a wavelength of approximately 525 nm for each of thesix increments of nickel sulfate standard solution. Th
22、en plot agraph on appropriate graph paper of the percent light transmis-sion against the known nickel concentration representing 0.2 to2.1 g of nickel deposit per square metre of surface. Theresulting graph, which should be a straight line, will be used toobtain nickel-coating masses from light tran
23、smission results.8. Determinations of Nickel Coating Masses8.1 Sampling a Nickel-Coated Steel Surface:8.1.1 Place the weighted, rubber ring assembly on thenickel-coated metal surface. Add 3 mL of warm (approxi-mately 120F (50C) HNO3(1+1).Allow the foaming reactionto proceed for about 10 s for light
24、nickel coatings and about 15s for heavier nickel coatings. If the warm acid does not react,scratch the steel surface or try another spot. After the acid hasfoamed for the prescribed time, add 5 mL of HCl (1+5) to stopthe foaming reaction. Withdraw the solution from the steelsurface with the aspirato
25、r into the calibrated flask. Rinse thetest area twice with water and retain the washings in the flask.8.1.2 Alternative methods for determining nickel are de-scribed in Test Methods E30, Sections 62 to 70 for thegravimetric method and Sections 71 to 73 for the volumetricmethod.8.2 Analytical Procedu
26、re:8.2.1 Add chemicals in the order given below to the solutionin the flask and mix thoroughly after each addition:Additions for 23-mm OpticalPath CellAAmount inOrder of UseAmmonium hydroxide (sp gr 0.90) 50 mLAmmonium persulfate 4 gDimethylglyoxime 10 mLDilute with water to 500 mLACells with other
27、optical path lengths are available.8.2.2 Filter a portion of the solution. Discard the first 10 to20 mL from the filter and collect a sufficient amount of filtratein the absorption cell for testing. Just before testing, set thewavelength as determined in accordance with Section 7 andadjust the instr
28、ument to 100 % transmission with a cell thatcontains only water. Place the cell containing the test solutionin the photometer and read the percent transmission.9. Calculation and Report9.1 Refer to the graph developed in Section 7. Determinethe mass of nickel that corresponds to the percent transmis
29、sionreading shown by the photometer. Report the results in gramsof nickel per square metre of steel surface.10. Precision and Bias10.1 The precision and bias of this test method is believed tobe within 0.000929 g/ft2(0.1 g/m2). Exact values are difficult toobtain because of sample inhomogeneity, and
30、 the effect of theacid etch on the rubber ring diameter (see 4.2.1).ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any
31、 such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are in
32、vited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not receive
33、d a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of t
34、his standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).NOTE 1The outer ring is a steel disk approximately 6 by12 in. (152by 13 mm), weighing approximately 312 lb (1.58 kg).FIG. 1 Detailed Drawing of Rubber RingC 715 90 (2006)2
