1、Designation: A877/A877M 16A877/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 adop
2、tion or, in the 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 round and shaped chrom
3、ium-silicon and chromium-silicon-vanadium alloysof steel valve spring wire, uniform in quality and temper, intended for the manufacture of valve springs and other springs requiringhigh-fatigue properties when used at moderately elevated temperatures. It is similar to the grade VD (referenced in EN 1
4、0270-2)intended for high fatigue levels. This wire shall be either in the annealed and cold-drawn or quenched and tempered condition asspecified by purchaser.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may no
5、t be exact equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result in non-conformance with the standard.2. Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testing of Steel ProductsA700 Guid
6、e for Packaging, Marking, and Loading Methods for Steel Products for ShipmentA751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel ProductsE8 Test Methods for Tension Testing of Metallic MaterialsE29 Practice for Using Significant Digits in Test Data to Determine Conformance w
7、ith SpecificationsE45 Test Methods for Determining the Inclusion Content of Steel2.2 European Standard:EN 10270-2 Steel Wire for Mechanical Springs Part 2: Oil-Hardened and Tempered Spring Steel Wire of Unalloyed andAlloyedSteels.33. Ordering Information3.1 It shall be the responsibility of the purc
8、haser to specify all requirements that are necessary for material under thisspecification. Such requirements are permitted to include, but are not limited to the following:3.1.1 Quantity (mass),3.1.2 Name of material (chromium-silicon alloy steel valve spring quality wire),3.1.3 Dimensions (Table 1
9、and Section 8),3.1.4 Condition (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 (Section 13), and3.1.8 ASTM designation and year of issue.NOTE 1A typical ordering description is as follows: 20 000-kg que
10、nched and tempered chromium-silicon alloy steel valve spring quality wire, size6.00 mm in 150-kg coils to A877/A877M dated _, or for inch-pound units, 40 000-lb quenched and tempered chromium-silicon alloy steel valve springquality wire, size 0.250 in. in 350-lb coils to A877/A877M dated _ .1 This s
11、pecification is under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and RelatedAlloys and is the direct responsibility of Subcommittee A01.03on Steel Rod and Wire.Current edition approved May 1, 2016March 15, 2017. Published May 2016March 2017. Originally approved in 1987. Last pre
12、vious edition approved in 20102016 asA877/A877M 10A877/A877M 16.1. DOI: 10.1520/A0877_A0877M-16. 10.1520/A0877_A0877M-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer
13、 to the standards Document Summary page on the ASTM website.3 Available from European Committee for Standardization, Rue de Stassart 36, B-1050 Brussels, Belgium.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been
14、 made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.
15、*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Materials and Manufacture4.1 The steel shall be made by a steel making process combined with secondary ladle refining
16、that is capable of satisfying theinclusion content requirements of this specification.4.2 The steel shall be continuously cast into blooms and rolled into billets.4.3 Billet conditioning shall precede wire rod manufacture. The resulting wire rods shall be of sufficient surface quality thatwhen combi
17、ned with a surface removal operation performed prior to or during the wire manufacturing operation the resulting wireshall satisfy the surface condition and decarburization requirements of this specification.4.4 The finished wire shall be free from detrimental pipe and undue segregation.5. Chemical
18、Composition5.1 The steel shall conform to the requirements for chemical composition specified in Table 2.5.2 Heat AnalysisEach heat of steel shall be analyzed by the manufacturer to determine the percentage of elements prescribedin Table 2. This analysis shall be made from a test specimen preferably
19、 taken during the pouring of the heat. When requested, thisshall be reported to the purchaser and shall conform to the requirements of Table 2.5.3 Product AnalysisAn analysis may be made by the purchaser from finished wire representing each heat of steel. Theaverage of all the separate determination
20、s made shall be within the limits specified in the analysis column. Individualdeterminations may vary to the extent shown in the product analysis tolerance column, except that the several determinations ofa single element in any one heat shall not vary both above and below the specified range.5.4 Fo
21、r referee purposes, Test Methods, Practices, and Terminology A751 shall be used.6. Mechanical Properties6.1 Annealed and Cold DrawnWhen purchased in the annealed and cold-drawn condition, the wire shall have been given asufficient amount of cold working to meet the purchasers coiling requirements an
22、d shall be in a suitable condition to respondproperly to heat treatment. In special cases the hardness, if desired, shall be stated in the purchase order.6.2 Quenched and TemperedWhen purchased in the quenched and tempered condition, the tensile strength and reduction ofarea (% R.A.) shall conform t
23、o the requirements prescribed in Table 3, Table 4, or Table 5. Percent reduction of the area (% R.A.)is not applicable to wire diameters under 2.0 mm 0.080 in.6.2.1 Tensile Strength of Shaped and Flat Rolled WireTensile strength of shaped and flat rolled wires shall conform to thesetables based on t
24、he conversion to equivalent round dimensions. Percent reduction of area is not applicable to flat rolled wires.NOTE 2Equivalent round definition: The cross sectional area of shaped wires converted to the round wire diameter.6.2.2 Tensile Strength VariationIn addition, the maximum tensile variation i
25、n a coil shall be 70 MPa 10.15 ksi.6.2.3 Number of TestsOne test specimen shall be taken from each end of every coil in a lot. Each heat in a given lot shall betested.NOTE 3Any specimen breaking in the tensile grips shall be discarded and a new specimen tested if the specified mechanical properties
26、are notachieved. If breakage in the tensile grips prevents conformance to percent reduction in area requirements, conformance to the wrap test (see 6.3) shallsuffice.6.2.4 Location of TestsTest specimens shall be taken from both ends of the coil.6.2.5 Test MethodThe tension test shall be made in acc
27、ordance with Test Methods and Definitions A370. For shaped wires,cross sectional area shall be calculated by either using the procedure in Test Methods E8 (Subsection 7.2.2) for uniform butnonsymmetrical cross-sections, or by measuring width and thickness and multiplying by a shape factor. Reduction
28、 of area forTABLE 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 0.03Over 4.0 to 9.5, incl 0.04 0.04Inch-Pound UnitsDiameter, in. Permissible Varia-tions, in.Permissible Out-ofR
29、ound, 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 0.0015A For purposes of determining conformance with this specification, all specifiedlimits are absolute as defined in recommended Practice E29.A877/A877M 172shaped wires shall be calcul
30、ated by using this shape factor. Measure the maximum and minimum dimension on the necked downsection and multiply by the shape factor to estimate the cross sectional area for use in the standard reduction of area calculation.6.2.5.1 Upon agreement between purchaser and supplier, the shape factor for
31、 the design provided by the wire mill shall bepermissible to be adopted for use. In other situations if the shape factor is not available from the wire mill, the shape factor shallbe calculated by measuring the cross sectional area in accordance with Test Methods E8 and dividing by the width and thi
32、ckness.6.3 Wrap Test:6.3.1 Grade ARound quenched and tempered or cold drawn wire 4.00 mm 0.157 in. or smaller in diameter shall wrap onitself as an arbor without breakage. Larger diameter wire up to and including 8.00 mm 0.315 in. in diameter shall wrap withoutbreakage on a mandrel twice the wire di
33、ameter. The wrap test is not applicable to wire over 8.00 mm 0.315 in. in diameter orto shaped and flat rolled wires.6.3.2 Grades B, C, or DRound of quenched and tempered wire 4.00 mm 0.1575 in. or smaller in diameter shall wrap ona mandrel twice the diameter without breakage. Larger diameter wire u
34、p to and including 8.00 mm 0.315 in. shall wrap withoutbreakage on a mandrel three times the wire diameter. The wrap test is not applicable to wire over 8.00 mm 0.315 in. in diameteror to shaped and flat rolled wires.TABLE 2 Chemical RequirementsAnalysis, %Grade A Chromium-SiliconGrade B Chromium-Si
35、licon-VanadiumGrade C Chrome-Silicon-Nickel-VanadiumGrade D Chrome-Silicon- Molybdenum-VanadiumProduct AnalysisTolerance, %Carbon 0.510.59 0.550.70 0.500.70 0.500.70 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 m
36、ax 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 0.050.15 0.050.15 0.02Nickel . . . . . . 0.200.40 . . . 0.03Molybdenum . . . . . . . . . 0.050.15 0.01A Product Analysis Tolerance for Grade A
37、 and B is 0.03 %.B Product Analysis Tolerance for Grade C other depths may be agreed upon.Number of allowable marks per coil, shall be agreed upon between the manufacturer and the purchaser. This test is not applicableto wire sizes below 2.5 mm 0.098 in.NOTE 4Inspection of certain cross sectional sh
38、apes may not be technically feasible.7. Metallurgical Requirements7.1 Surface Condition:7.1.1 The surface of the wire as received shall be free of imperfections such as pits, die marks, scratches, seams, and otherdefects tending to impair the fatigue value of the springs.7.1.2 Number of TestsOne tes
39、t specimen shall be taken from each end of every coil.7.1.3 Test MethodThe surface shall be examined after etching in a solution of equal parts of hydrochloric acid and water thathas been heated to approximately 80C for up to 2 min in order to remove the oxide scale layer from the wire surface. Test
40、 endsshall 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(carbon-free) areas when examined at a magnification of 100 diameters. Partial decarburization shall not exceed a depth
41、of 0.025mm 0.0010 in. on wire 5.00 mm 0.197 in. and smaller, or 0.038 mm 0.0015 in. on larger than 5.00 mm 0.197 in.NOTE 5There are certain situations (in other words, where a minimum residual stress value after shot peening is specified, or a minimum surfacehardness after nitriding is specified) wh
42、ere allowable levels of decarburization may impair the ability to achieve the desired result. In such case, it isincumbent on the purchaser to make special arrangements with the supplier for a restricted level of allowable decarburization.7.2.2 To reveal the decarburization more accurately in untemp
43、ered wire, the specimen shall be hardened and tempered beforemicroscopic examination. Prior to hardening, the specimen shall be filed flat on one side enough to reduce the diameter at least20 %. The subsequent mounted specimen shall show the flattened section, as well as the original wire edge. Any
44、decarburizationon this flattened section shall necessitate a new specimen for examination.7.2.3 Number of TestsOne test specimen shall be taken for each five coils, or fraction thereof, in a lot.7.2.4 Location of TestsTest specimens may be taken from either end of the coil.7.3 Inclusion Content:7.3.
45、1 The inclusion content of the wire or wire rod in the worst case shall not exceed the limits shown in Table 6 as describedin Test Methods E45, Plate I-r, Method D, except that alternate methodologies are acceptable upon agreement between purchaserand supplier provided minimum requirements are not l
46、ower than those of Test Methods E45, Method D.7.3.1.1 If any coil exceeds the limits listed in Table 6, all coils in the lot will be inspected. Each coil that fails to meet therequirements will be rejected.7.3.2 Number of TestsOne test specimen shall be taken for each 10 coils, or fraction thereof,
47、in the lot.7.3.3 Location of TestsTest specimens may be taken from either end of the coil.7.3.4 Test MethodA longitudinal section approximately 12.7 mm 0.5 in. long shall be ground to the centerline and properlymounted and polished. Examination shall be made in accordance with Test Methods E45.7.3.5
48、 Upon agreement by the purchaser and supplier, the inclusion requirements may be waived.8. Dimensions and Permissible Variations8.1 The permissible variations in the diameter of the wire shall be as specified in Table 1.Any definition of shape wire tolerancesshall be agreed upon by the manufacturer
49、and the purchaser.8.2 Number of TestsOne test specimen shall be taken from each end of every coil.9. Workmanship, Finish, and Appearance9.1 Annealed and Cold DrawnThe wire shall not be kinked or improperly cast. To test for cast, a few convolutions of wireshall be cut loose from the coil and placed on a flat surface. The wire shall lie substantially flat on itself and not spring up nor showa wavy condition.TABLE 6 Maximum Inclusion ContentNOTE 1The surface zone is from the wire sur
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