ASTM A877A877M-17 Standard Specification for Steel Wire, Chromium-Silicon Alloys, Chrome-Silicon-Vanadium Alloy Valve Spring Quality.pdf

1、Designation: A877/A877M 17Standard Specification forSteel Wire, Chromium-Silicon Alloys, Chrome-Silicon-Vanadium Alloy Valve Spring Quality1This standard is issued under the fixed designation A877/A877M; the number immediately following the designation indicates the yearof original adoption or, in t

2、he case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers the highest quality of roundand shaped chromium-silicon an

3、d chromium-silicon-vanadiumalloys of steel valve spring wire, uniform in quality and temper,intended for the manufacture of valve springs and other springsrequiring high-fatigue properties when used at moderatelyelevated temperatures. It is similar to the grade VD (referencedin EN 10270-2) intended

4、for high fatigue levels. This wire shallbe either in the annealed and cold-drawn or quenched andtempered condition as specified by purchaser.1.2 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 equival

5、ents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.2. Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA700 Guide for Packaging, Mark

6、ing, and Loading Methodsfor Steel Products for ShipmentA751 Test Methods, Practices, and Terminology for Chemi-cal Analysis of Steel ProductsE8 Test Methods for Tension Testing of Metallic MaterialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE45

7、Test Methods for Determining the Inclusion Content ofSteel2.2 European Standard:EN 10270-2 Steel Wire for Mechanical Springs Part 2:Oil-Hardened and Tempered Spring Steel Wire of Unal-loyed and Alloyed Steels.33. Ordering Information3.1 It shall be the responsibility of the purchaser to specifyall r

8、equirements that are necessary for material under thisspecification. Such requirements are permitted to include, butare not limited to the following:3.1.1 Quantity (mass),3.1.2 Name of material (chromium-silicon alloy steel valvespring quality wire),3.1.3 Dimensions (Table 1 and Section 8),3.1.4 Con

9、dition (Section 6),3.1.5 Packaging (Section 14),3.1.6 Heat analysis report, if requested (5.2),3.1.7 Certification or test report, or both, if specified (Sec-tion 13), and3.1.8 ASTM designation and year of issue.NOTE 1A typical ordering description is as follows: 20 000-kgquenched and tempered chrom

10、ium-silicon alloy steel valve spring qualitywire, size 6.00 mm in 150-kg coils to A877/A877M dated _, or forinch-pound units, 40 000-lb quenched and tempered chromium-siliconalloy steel valve spring quality wire, size 0.250 in. in 350-lb coils toA877/A877M dated _ .4. Materials and Manufacture4.1 Th

11、e steel shall be made by a steel making processcombined with secondary ladle refining that is capable ofsatisfying the inclusion content requirements of this specifica-tion.4.2 The steel shall be continuously cast into blooms androlled into billets.4.3 Billet conditioning shall precede wire rod manu

12、facture.The resulting wire rods shall be of sufficient surface qualitythat when combined with a surface removal operation per-formed prior to or during the wire manufacturing operation theresulting wire shall satisfy the surface condition and decarbur-ization requirements of this specification.4.4 T

13、he finished wire shall be free from detrimental pipeand undue segregation.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.03 on Steel Rod and Wire.Current edition approved March 15, 20

14、17. Published March 2017. Originallyapproved in 1987. Last previous edition approved in 2016 as A877/A877M 16.DOI: 10.1520/A0877_A0877M-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume

15、 information, refer to the standards Document Summary page onthe ASTM website.3Available from European Committee for Standardization, Rue de Stassart 36,B-1050 Brussels, Belgium.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO B

16、ox C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by

17、the World Trade Organization Technical Barriers to Trade (TBT) Committee.15. Chemical Composition5.1 The steel shall conform to the requirements for chemicalcomposition specified in Table 2.5.2 Heat AnalysisEach heat of steel shall be analyzed bythe manufacturer to determine the percentage of elemen

18、tsprescribed in Table 2. This analysis shall be made from a testspecimen preferably taken during the pouring of the heat.When requested, this shall be reported to the purchaser andshall conform to the requirements of Table 2.5.3 Product AnalysisAn analysis may be made by thepurchaser from finished w

19、ire representing each heat of steel.The average of all the separate determinations made shall bewithin the limits specified in the analysis column. Individualdeterminations may vary to the extent shown in the productanalysis tolerance column, except that the several determina-tions of a single eleme

20、nt in any one heat shall not vary bothabove and below the specified range.5.4 For referee purposes, Test Methods, Practices, andTerminology A751 shall be used.6. Mechanical Properties6.1 Annealed and Cold DrawnWhen purchased in theannealed and cold-drawn condition, the wire shall have beengiven a su

21、fficient amount of cold working to meet the purchas-ers coiling requirements and shall be in a suitable condition torespond properly to heat treatment. In special cases thehardness, if desired, shall be stated in the purchase order.6.2 Quenched and TemperedWhen purchased in thequenched and tempered

22、condition, the tensile strength andreduction of area (% R.A.) shall conform to the requirementsprescribed in Table 3, Table 4,orTable 5. Percent reduction ofthe area (% R.A.) is not applicable to wire diameters under2.0 mm 0.080 in.6.2.1 Tensile Strength of Shaped and Flat Rolled WireTensile strengt

23、h of shaped and flat rolled wires shall conform tothese tables based on the conversion to equivalent rounddimensions. Percent reduction of area is not applicable to flatrolled wires.NOTE 2Equivalent round definition: The cross sectional area ofshaped wires converted to the round wire diameter.6.2.2

24、Tensile Strength VariationIn addition, the maximumtensile variation in a coil shall be 70 MPa 10.15 ksi.6.2.3 Number of TestsOne test specimen shall be takenfrom each end of every coil in a lot. Each heat in a given lotshall be tested.NOTE 3Any specimen breaking in the tensile grips shall be discard

25、edand a new specimen tested if the specified mechanical properties are notachieved.6.2.4 Location of TestsTest specimens shall be taken fromboth ends of the coil.6.2.5 Test MethodThe tension test shall be made inaccordance with Test Methods and Definitions A370. Forshaped wires, cross sectional area

26、 shall be calculated by eitherusing the procedure in Test Methods E8 (Subsection 7.2.2) foruniform but nonsymmetrical cross-sections, or by measuringwidth and thickness and multiplying by a shape factor. Reduc-tion of area for shaped wires shall be calculated by using thisshape factor. Measure the m

27、aximum and minimum dimensionon the necked down section and multiply by the shape factor toestimate the cross sectional area for use in the standardreduction of area calculation.6.2.5.1 Upon agreement between purchaser and supplier,the shape factor for the design provided by the wire mill shallbe per

28、missible to be adopted for use. In other situations if theshape factor is not available from the wire mill, the shapefactor shall be calculated by measuring the cross sectional areain accordance with Test Methods E8 and dividing by the widthand thickness.6.3 Wrap Test:6.3.1 Grade ARound quenched and

29、 tempered or colddrawn wire 4.00 mm 0.157 in. or smaller in diameter shallwrap on itself as an arbor without breakage. Larger diameterwire up to and including 8.00 mm 0.315 in. in diameter shallwrap without breakage on a mandrel twice the wire diameter.The wrap test is not applicable to wire over 8.

30、00 mm0.315 in. in diameter or to shaped and flat rolled wires.6.3.2 Grades B, C, or DRound of quenched and temperedwire 4.00 mm 0.1575 in. or smaller in diameter shall wrap ona mandrel twice the diameter without breakage. Larger diam-eter wire up to and including 8.00 mm 0.315 in. shall wrapwithout

31、breakage on a mandrel three times the wire diameter.The wrap test is not applicable to wire over 8.00 mm0.315 in. in diameter or to shaped and flat rolled wires.6.3.3 Number of TestsOne test specimen shall be taken foreach five coils, or fraction thereof, in a lot. Each heat in a givenlot shall be t

32、ested.6.3.4 Location of TestsTest specimens shall be taken fromeither end of the coil.6.3.5 Test MethodThe wrap test shall be made in accor-dance with Test Methods and Definitions A370.6.4 Special Surface InspectionThe entire length of everycoil shall be inspected for surface imperfections with a ro

33、tatingand stationary probe eddy current defect analyzer, or equiva-lent system. Imperfections deeper than 0.04 mm 0.0016 in.shall be properly marked so the purchaser has the ability toidentify and discard that length of wire; other depths may beagreed upon. Number of allowable marks per coil, shall

34、beagreed upon between the manufacturer and the purchaser. Thistest is not applicable to wire sizes below 2.5 mm 0.098 in.TABLE 1 Permissible Variations in Wire DiameterASI UnitsDiameter, mm Permissible Varia-tions, mmPermissible Out-ofRound, mm0.5 to 2.0, incl 0.02 0.02Over 2.0 to 4.0, incl 0.03 0.0

35、3Over 4.0 to 9.5, incl 0.04 0.04Inch-Pound UnitsDiameter, in. Permissible Varia-tions, in.Permissible Out-ofRound, in.0.020 to 0.075, incl 0.0008 0.0008Over 0.075 to 0.148, incl 0.001 0.001Over 0.148 to 0.375, incl 0.0015 0.0015AFor purposes of determining conformance with this specification, all sp

36、ecifiedlimits are absolute as defined in recommended Practice E29.A877/A877M 172NOTE 4Inspection of certain cross sectional shapes may not betechnically feasible.7. Metallurgical Requirements7.1 Surface Condition:7.1.1 The surface of the wire as received shall be free ofimperfections such as pits, d

37、ie marks, scratches, seams, andother defects tending to impair the fatigue value of the springs.7.1.2 Number of TestsOne test specimen shall be takenfrom each end of every coil.7.1.3 Test MethodThe surface shall be examined afteretching in a solution of equal parts of hydrochloric acid andwater that

38、 has been heated to approximately 80C for up to2 min in order to remove the oxide scale layer from the wiresurface. Test ends shall be examined using 10 magnification.7.2 Decarburization:7.2.1 Transverse sections of the wire properly mounted,polished, and etched shall show no completely decarburized

39、(carbon-free) areas when examined at a magnification of 100diameters. Partial decarburization shall not exceed a depth of0.025 mm 0.0010 in. on wire 5.00 mm 0.197 in. andsmaller, or 0.038 mm 0.0015 in. on larger than 5.00 mm0.197 in.NOTE 5There are certain situations (in other words, where a minimum

40、residual stress value after shot peening is specified, or a minimum surfacehardness after nitriding is specified) where allowable levels of decarbur-ization may impair the ability to achieve the desired result. In such case,it is incumbent on the purchaser to make special arrangements with thesuppli

41、er for a restricted level of allowable decarburization.TABLE 2 Chemical RequirementsAnalysis, %Grade A Chromium-SiliconGrade B Chromium-Silicon-VanadiumGrade C Chrome-Silicon-Nickel-VanadiumGrade D Chrome-Silicon- Molybdenum-VanadiumProduct AnalysisTolerance, %Carbon 0.510.59 0.550.70 0.500.70 0.500

42、.70 0.02Manganese 0.500.80 0.500.80 0.701.00 0.300.60 0.04Phosphorus 0.025 max 0.025 max 0.020 max 0.020 max 0.005Sulfur 0.025 max 0.025 max 0.020 max 0.020 max 0.005Silicon 1.201.60 1.201.65 1.802.20 1.802.20 0.05Chromium 0.600.80 0.500.80 0.851.05 0.801.00 0.03A/ 0.05BVanadium . . . 0.080.25 0.050

43、.15 0.050.15 0.02Nickel . . . . . . 0.200.40 . . . 0.03Molybdenum . . . . . . . . . 0.050.15 0.01AProduct Analysis Tolerance for Grade A and B is 0.03 %.BProduct Analysis Tolerance for GradeC&Dis0.05%.“. . .” indicates that there is no requirement and that these elements are not required to be repor

44、ted.TABLE 3 TensileAand % R.A. RequirementsGrade A (Chrome Silicon)SI UnitsDiameter, mm MPa, min MPa, max Min % R.A.BC0.5 2100 2280 . . .1.0 2070 2240 . . .1.5 2030 2210 . . .2.0 2000 2140 453.0 1930 2070 453.75 1900 2030 404.5 1830 1970 405.0 1810 1950 405.7 1800 1930 406.3 1760 1900 407.9 1730 186

45、0 409.5 1690 1830 40Inch-Pound UnitsDiameter, in. ksi, min ksi, max Min % R.A.BC0.020 305 330 . . .0.040 300 325 . . .0.060 295 320 . . .0.080 290 310 450.120 280 300 450.148 275 295 400.177 265 285 400.200 263 283 400.225 260 280 400.250 255 275 400.312 250 270 400.375 245 265 40ATensile strength v

46、alues for intermediate diameters shall be interpolated.BFor intermediate diameters, the % R.A. requirement shall be that of the nextlarger wire diameter.C“. . .” indicates that there is no requirement.TABLE 4 TensileAand % R.A. RequirementsGrade B (Chrome Silicon Vanadium)SI UnitsDiameter, mm MPa, m

47、in MPa, max Min % R.A.BC0.5 2200 2380 . . .1.0 2170 2340 . . .1.5 2140 2300 . . .2.0 2100 2240 403.0 2070 2200 403.75 2030 2170 354.5 2000 2140 355.0 1970 2100 355.7 1930 2070 356.3 1900 2030 357.9 1860 2000 359.5 1830 1970 35Inch-Pound UnitsDiameter, in. ksi, min ksi, max Min % R.A.BC0.020 320 345

48、. . .0.040 315 340 . . .0.060 310 335 . . .0.080 305 325 400.120 300 320 400.148 295 315 350.177 290 310 350.200 285 305 350.225 280 300 350.250 275 295 350.312 270 290 350.375 265 285 35ATensile strength values for intermediate diameters shall be interpolated.BFor intermediate diameters, the % R.A.

49、 requirement shall be that of the nextlarger wire diameter.C“. . .” indicates that there is no requirement.A877/A877M 1737.2.2 To reveal the decarburization more accurately inuntempered wire, the specimen shall be hardened and temperedbefore microscopic examination. Prior to hardening, the speci-men shall be filed flat on one side enough to reduce thediameter at least 20 %. The subsequent mounted specimenshall show the flattened section, as well as the original wireedge. A