1、Designation: A 518/A 518M 99 (Reapproved 2003)Standard Specification forCorrosion-Resistant High-Silicon Iron Castings1This standard is issued under the fixed designation A 518/A 518M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript 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 This specification cov
3、ers high-silicon cast iron castingsintended for corrosion-resistant service.1.2 This specification covers three grades as shown in Table1. Selection of grade depends on the corrosive service to beexperienced by the casting. All three grades are suited forapplication in severe corrosive environments.
4、 However, Grade2 is particularly suited for application in strong chlorideenvironments, and Grade 3 is recommended for impressedcurrent anodes.1.3 The values stated in either inch-pound units or SI unitsare to be regarded separately as standard. Within the text, theSI units are shown in brackets. Th
5、e values stated in eachsystem are not exact equivalents; therefore, each system shallbe used independently of the other. Combining values from thetwo systems may result in nonconformance with the specifi-cation.1.4 The following safety hazards caveat pertains only to thetest method portion, Section
6、9, of this specification: Thisstandard does not purport to address all of the safety concerns,if any, associated with its use. It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to
7、use.2. Referenced Documents2.1 ASTM Standards:2A 438 Test Method for Transverse Testing of Gray Cast IronE 350 Test Methods for Chemical Analysis of Carbon Steel,Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, andWrought IronE 351 Test Methods for Chemical Analysis of Cast IronAll Types3. Ord
8、ering Information3.1 Orders for material under this specification shall includethe following information:3.1.1 ASTM designation and year of issue.3.1.2 Grade of high-silicon cast iron (see Section 5).3.1.3 Number of castings.3.1.4 Approximate weight of the casting.3.1.5 Drawing showing the size, sha
9、pe, dimensions, andfinishing details. The drawing should indicate any criticaldimensions and should give the allowable tolerances on alldimensions and on the accumulation of dimensions. If thepurchaser supplies the pattern, the dimensions of the castingshall conform to those predicted by the pattern
10、.3.1.6 Options in this specification, including:3.1.6.1 The status of the heat treatment of the castings whenshipped by the manufacturer (see Section 7).3.1.6.2 If the chemical analysis and mechanical test resultsare to be reported to the purchaser (see Section 14).3.1.6.3 If a transverse test is re
11、quired (see 8.1).3.1.6.4 If hydraulic testing is required, and, if required, thetest pressure and the leakage permitted (see 8.2).3.1.6.5 Any special packing, markings, etc.4. Method of Manufacture4.1 The alloy may be produced by any melting and castingprocess, or combination of processes, capable o
12、f meeting thechemical composition and mechanical properties specified.1This specification is under the jurisdiction of ASTM Committee A04 on IronCastings and is the direct responsibility of Subcommittee A04.01 on Grey and WhiteIron Castings.Current edition approved Oct. 10, 1999. Published December
13、1999. Originallyapproved in 1964. Last previous edition approved in 1999 as A 518 99.2For 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
14、page onthe ASTM website.TABLE 1 Chemical CompositionElement Composition, Weight %Grade 1 Grade 2 Grade 3Carbon 0.651.10 0.751.15 0.701.10Manganese 1.50, max 1.50, max 1.50, maxSilicon 14.2014.75 14.2014.75 14.2014.75Chromium 0.50, max 3.255.00 3.255.00Molybdenum 0.50, max 0.400.60 0.20, maxCopper 0.
15、50, max 0.50, max 0.50, max1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Chemical Composition5.1 High-silicon iron castings are produced in one of threegrades, as given in Table 1 of this specification.6. Chemical Analysis6.1 He
16、at AnalysisChemical analysis of each heat (or eachtap, if from a continuous melting operation) shall be made bythe manufacturer to determine the percentages of the elementsspecified in Table 1. The analysis shall be made from a testsample cast during the pouring of the heat (or tap). Thechemical com
17、position thus determined shall conform to therequirements specified for that grade in Table 1.6.2 Product AnalysisA product analysis may be made bythe purchaser from material representing each heat, lot, orcasting. The sample for such analysis shall be taken as desiredby the purchaser. The chemical
18、composition thus determinedshall meet the requirements for the grade specified.6.3 Routine Analysis MethodsSpectrometric and otherinstrumental methods or wet chemical laboratory methods areacceptable for routine and control determinations, but shall bestandardized against and give essentially the sa
19、me results as themethods specified in 6.4.6.4 Reference Analysis Methods:6.4.1 Silicon:6.4.1.1 Analyze samples soluble when processed in accor-dance with Test Methods E 350, by that method, except asfollows:(a) (a) The sample weight shall be 0.3 g with a weighttolerance of 60.1 mg.(b) (b) Pulverize
20、one or more pieces of the sample until theentire material in the piece or pieces passes through a 100-mesh screen.(c) (c) Dissolve the sample in 25 mL of perchloric acid.6.4.1.2 Analyze samples that are not soluble when pro-cessed in accordance with 6.4.1.1 in accordance with AnnexA1.6.4.2 Molybdenu
21、m:6.4.2.1 Mill, lathe, or pulverize the sample to pass througha 100-mesh sieve. If the sample is soluble when processed inaccordance with Test Methods E 350, use this method.6.4.2.2 If the sample is not acid-soluble when processed inaccordance with 6.4.2.1, proceed as follows:(a) (a) Use the appropr
22、iate weight of sample in accordancewith 6.4.2.1 instead of the weight given in A1.2.3 of Annex A1.(b) (b) Fuse the sample in accordance with A1.2.1 andA1.2.2 and A1.2.4-A1.2.12 of Annex A1.(c) (c) Add the amount of dissolving acid(s), specified inthe sections in Molybdenum by the Photometric Method
23、inTest Methods E 350, heat to fumes of perchloric acid. Proceedin accordance with Test Methods E 350.6.4.3 CarbonDetermine carbon in accordance with sec-tions on Carbon, Total, by the Combustion GravimetricMethod, in Test Methods E 350.6.4.4 Manganese:6.4.4.1 Mill, lathe, or pulverize the sample to
24、pass througha 100-mesh sieve.6.4.4.2 Determine manganese in accordance with the sec-tions on Manganese by the Peroxydisulfate-Arsenite Titrimet-ric Method in Test Methods E 350. Add hydrofluoric acid asrequired for complete solution of the (HF) sample.6.4.5 Chromium:6.4.5.1 Mill, lathe, or pulverize
25、 the sample to pass througha 100-mesh sieve.6.4.5.2 Determine chromium in accordance with the sec-tions on Chromium by the Peroxydisulfate-Oxidation Titrimet-ric Method in Test Methods E 350, except dissolve the sampleas follows:(a) (a) Place the appropriate amount of weighed sampleinto a 600-mL Gri
26、ffin beaker or 500-mL volumetric flask. Add20 mL of nitric acid (HNO3) and carefully add HF, dropwise,until the reaction ceases. A TFE-fluorocarbon beaker may beused if desired.(b) (b) Add30mLof1+1sulfuric acid (H2SO4),5mLofphosphoric acid (H3PO4), and boil until light fumes of H2SO4are present and
27、the sample is completely dissolved.(c) (c) Cool the solution, add 150 mL of water, heat todissolve if necessary, and continue as in Test Methods E 350.6.4.6 Copper:6.4.6.1 Mill, lathe, or pulverize the sample to pass througha 100-mesh sieve.6.4.6.2 Determine the copper in accordance with the sec-tio
28、ns on Copper by the Sulfide Precipitation-ElectrodepositionGravimetric Method in Test Methods E 350, or6.4.6.3 Determine the copper in accordance with the sec-tions on Copper by the Neocuproine Photometric Method, inTest Methods E 350. Add HF as required for complete solutionof the sample.7. Heat Tr
29、eatment7.1 High-silicon iron castings are generally used in theheat-treated (stress-relieved) condition. Small castings ofsimple configuration not conducive to high-residual stressesmay be used in the as-cast condition. If the castings are to besupplied in the stress-relieved condition, the purchase
30、r must sospecify.7.2 At its option, the foundry may heat treat the castings toremove stresses without the purchaser so specifying.7.3 If used, the stress-relieving heat treatment shall be asfollows:7.3.1 Heat at a rate that will not crack the castings.7.3.2 Hold the castings at a minimum temperature
31、 of1600F 870C for a minimum period of 1 h/in. mm ofmaximum section thickness, except that in no case shall theholding period be less than 2 h.7.3.3 Cool the castings to 400F 205C maximum at a ratenot faster than 100F 55C/15 min.7.3.4 From 400F 205C to ambient temperature, thecastings may be cooled i
32、n still ambient air.8. Mechanical Requirements8.1 Transverse Bend Test:8.1.1 When specified by the purchaser, the silicon-iron alloyshall be given a transverse bend test. The specimen tested shallmeet the test requirements prescribed in Table 2.A 518/A 518M 99 (2003)28.1.2 When transverse bend tests
33、 are specified, test barsshall be made and tested from each heat (or ladle in the case ofcontinuous melting) from which the castings are poured.8.1.3 The test bars shall be heat treated in the productionfurnaces to the same procedure as the castings.8.1.4 Each test bar shall be permanently marked wi
34、th theheat or ladle number from which it was poured. Marking shallbe accomplished with cast digits, with a vibratory markingtool, or with a felt-point pen using indelible ink.8.2 Hydrostatic TestWhen specified by the purchaser,subject the castings for critical applications involving pressureor vacuu
35、m conditions to a hydrostatic pressure test at aminimum of 40 psig 275 kPa. Any leak revealed by this testshall be cause for rejection of the casting.9. Transverse Bend Test Method9.1 When a requirement for transverse bend tests has beenagreed upon between the purchaser and the manufacturer, themanu
36、facturer shall test transverse bend bar(s) from each heat.9.2 Conduct the transverse bend test in accordance withMethod A 438, except as follows:9.2.1 Do not machine the specimen.9.2.2 The specimen shall be sufficiently smooth, round, andstraight to permit testing without machining.9.2.3 Produce the
37、 specimen in accordance with Fig. 1.9.2.4 The specimen shall conform to the dimensions shownin Fig. 2.9.2.5 Report the actual breaking load without use of acorrection factor. The requirements of Table 2 allow fordeviation due to variations in test bar diameter. In the samesense, measure and report t
38、he deflection at fracture withoutcorrection.9.2.6 Apply the load at a rate such that a 0.025-in. 0.65-mm deflection is produced in 50 to 70 s. Continue loading atthe same head-movement rate until the specimen fractures.10. Workmanship, Finish, and Appearance10.1 The workmanship and finish shall be a
39、s agreed uponbetween the manufacturer and the purchaser.11. Number of Tests and Retests11.1 If a valid test specimen fails to conform to thisspecification, two retests shall be made. If either retest fails toTABLE 2 Transverse Bend Test Minimum RequirementsNOTE 1Test bars are to be tested on support
40、s 12 in. 3.5 mm apart.Load at center, min, lbf N 930 4090Deflection at center, min, in. mm 0.026 0.66FIG. 1 Suggested Pattern for Transverse Bend Test Bar, Cast Horizontally, 1.20 in. 30.5 mm in DiameterA 518/A 518M 99 (2003)3conform to this specification, the castings represented by thesetest bars
41、shall be rejected.11.2 If after testing, a test specimen shows evidence of adefect, the results of the test may be regarded as invalid andanother test made.11.3 In the absence of further separately cast test bars, themanufacturer shall have the option of submitting test barssectioned from an agreed-
42、upon position in the castings.11.4 If reheat treatment is required to meet the specification,castings and their representative test bars shall be reheat treatedtogether. Testing will then proceed as in 11.1, 11.2, and 11.3.12. Inspection12.1 When specified in the purchase order, the inspectorreprese
43、nting the purchaser shall have access to the materialsubject to inspection for the purpose of witnessing the selectionof the samples, the preparation of the test pieces, and theperformance of the test(s). For such tests, the inspector shallhave the right to indicate the pieces from which the samples
44、will be taken in accordance with the provisions of thisspecification.12.2 The manufacturer shall inspect the material covered bythis specification prior to shipment and, upon request, shallfurnish the purchaser with a certification of test(s).13. Rejection and Rehearing13.1 RejectionAny rejection ba
45、sed on test reports shall bereported to the manufacturer within 30 days from the receipt ofthe test report by the purchaser. The manufacturer shall beadvised within one week of purchasers discovery of materialthat contains injurious defects. The purchaser shall hold thematerial a minimum of 30 days
46、pending action by the manu-facturer.13.2 RehearingSamples tested in accordance with thisspecification that represent rejected material shall be preservedfor two weeks from the date of the test report. In case ofdissatisfaction with the results of the test, the manufacturermay make a claim for a rehe
47、aring within that time.14. Certification14.1 When specified by the purchaser, the manufacturershall provide the purchaser with a certification stating that thecastings meet the specified requirements. The certification shallinclude the results of any chemical analyses and mechanicaltests.15. Product
48、 Marking15.1 The trademark of the manufacturer shall be legibly caston each casting.ANNEX(Mandatory Information)A1. SILICON BY THE FUSION-HYDROCHLORIC ACID DEHYDRATION METHODA1.1 This method may be used for the referee determina-tion of silicon in high-silicon cast irons. All reagents are to bereage
49、nt grade. All water is to be deionized or triple-distilled.A1.2 Procedure:A1.2.1 Preparation of SamplePulverize a representativeportion of the sample until the entire portion will pass a No.100 sieve.A1.2.2 Weigh8gofanhydrous sodium carbonate into a50-mL nickel crucible.A1.2.3 Weigh 0.5 g of pulverized sample and place on topof the sodium carbonate in the nickel crucible.A1.2.4 Weigh4gofsodium peroxide and place on top ofthe sample in the nickel crucible.A1.2.5 Stir carefully with a glass rod until the mixture ishomogeneous.NOTE
