1、Designation: F 568M 04METRICStandard Specification forCarbon and Alloy Steel Externally Threaded MetricFasteners1This standard is issued under the fixed designation F 568M; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This specification covers chemica
3、l and mechanical re-quirements for nine property classes of carbon and alloy steelexternally threaded metric fasteners in nominal thread diam-eters M1.6 through M100 suited for use in general engineeringapplications.1.2 This specification does not cover dimensional require-ments for fasteners of any
4、 property class. When referencingthis specification for procurement purposes, it is mandatorythat size, type, style, and any special dimensions of the productbe additionally specified.1.2.1 In case of any conflict in requirements, the require-ments of the individual product specification shall take
5、prece-dence over those of this general specification.1.2.2 The purchaser may specify additional requirementswhich do not negate any of the provisions of this generalspecification or of the individual product specification. Suchadditional requirements, the acceptance of which are subject tonegotiatio
6、n with the supplier, must be included in the orderinformation (see Section 3).1.3 Requirements for seven of the nine property classes, 4.6,4.8, 5.8, 8.8, 9.8, 10.9, and 12.9, are essentially identical withrequirements given for these classes in ISO 898-1. The othertwo, 8.8.3 and 10.9.3, are not reco
7、gnized in ISO standards.1.4 Classes 8.8.3 and 10.9.3 bolts, screws, and studs haveatmospheric corrosion resistance and weathering characteris-tics comparable to those of the steels covered in SpecificationA 588/A 588M. The atmospheric corrosion resistance of thesesteels is substantially better than
8、that of carbon steel with orwithout copper addition. See 5.2. When properly exposed tothe atmosphere, these steels can be used bare (uncoated) formany applications.1.5 When agreed on by the purchaser, Class 5.8 fastenersmay be supplied when either Classes 4.6 or 4.8 are ordered;Class 4.8 may be supp
9、lied when Class 4.6 is ordered; Class8.8.3 may be supplied when Class 8.8 is ordered; and Class10.9.3 may be supplied when Class 10.9 is ordered.1.6 The product size range for which each property class isapplicable is given in Table 1 and Table 2 on chemicalcomposition requirements, and the mechanic
10、al requirementstable (see Table 3).1.7 Appendix X1 gives conversion guidance to assist de-signers and purchasers in the selection of a suitable propertyclass.1.8 Appendix X2 explains the significance of the propertyclass designation numerals.2. Referenced Documents2.1 ASTM Standards:2A 153/A 153M Sp
11、ecification for Zinc Coating (Hot-Dip) onIron and Steel HardwareA 307 Specification for Carbon Steel Bolts and Studs,60 000 psi Tensile StrengthA 325 Specification for Structural Bolts, Steel, HeatTreated, 120/105 ksi Minimum Tensile StrengthA 325M Specification for Structural Bolts, Steel, HeatTrea
12、ted 830 Mpa Minimum Tensile Strength MetricA 354 Specification for Quenched and Tempered AlloySteel Bolts, Studs, and Other Externally Threaded Fasten-ersA 449 Specification for Quenched and Tempered SteelBolts and StudsA 490 Specification for Structural Bolts, Alloy Steel, HeatTreated, 150 ksi Mini
13、mum Tensile StrengthA 490M Specification for High-Strength Steel Bolts,Classes 10.9 and 10.9.3, for Structural Steel Joints MetricA 574 Specification for Alloy Steel Socket-Head CapScrews1This specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility
14、of Subcommittee F16.02 on Steel Bolts,Nuts, Rivets and Washers.Current edition approved Aug. 1, 2004. Published August 2004. Originallyapproved in 1979. Last previous edition approved in 2002 as F 568M 02.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer S
15、ervice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1
16、9428-2959, United States.TABLE 1 Chemical Composition RequirementsPropertyClassNominal ProductDiameter, mmMaterial and TreatmentProduct Analysis Element (% by weight) TemperingTemperature, CCMnBPSMin Max Min Min Max Max Min4.6 M5M100 low or medium carbon steel . . . 0.55 . . . . . . 0.048 0.058 . .
17、.4.8 M1.6M16 low or medium carbon steel, partially or fully annealed as required . . . 0.55 . . . . . . 0.048 0.058 . . .5.8 M5M24 low or medium carbon steel, cold worked 0.13 0.55 . . . . . . 0.048 0.058A.8.8 M20M80 medium carbon steel, product is quenched and temperedB0.25 0.55 . . . . . . 0.048 0
18、.058C4258.8 M20M36 low carbon martensite steel, product is quenched and temperedD0.15 0.40 0.74 0.0005 0.048 0.058 4258.8.3 M20M36 atmospheric corrosion resistant steel, product is quenched andtemperedsee Table 2 4259.8 M1.6M16 medium carbon steel, product is quenched and tempered 0.25 0.55 . . . .
19、. . 0.048 0.058 4259.8 M1.6M16 low carbon martensite steel, product is quenched and temperedD0.15 0.40 0.74 0.0005 0.048 0.058 42510.9 M5M20 medium carbon steel, product is quenched and temperedE,F0.25 0.55 . . . . . . 0.048 0.058 42510.9 M5M100 medium carbon alloy steel, product is quenched and tem
20、peredE0.20 0.55 . . . . . . 0.040 0.045 42510.9 M5M36 low carbon martensite steel, product is quenched and temperedE,F0.15 0.40 0.74 0.0005 0.048 0.058 34010.9.3 M16M36 atmospheric corrosion resistant steel, product is quenched andtemperedEsee Table 2 42512.9 M1.6M100 alloy steel, product is quenche
21、d and temperedE,G0.31 0.65 . . . . . . 0.045 0.045 380AFor studs only, sulfur content may be 0.33 %, max.BAt the manufacturers option, medium-carbon-alloy steel may be used for nominal thread diameters over M24.CFor studs only, sulfur content may be 0.13 %, max.DProducts made using this material sha
22、ll be specially identified as specified in Section 15.ESteel for Classes 10.9, 10.9.3, and 12.9 products shall be fine grain and have a hardenability that will achieve a structure of approximately 90 % martensite at the centerof a transverse section one diameter from the threaded end of the product
23、after oil quenching.FCarbon steel may be used at the option of the manufacturer for products of nominal thread diameters M12 and smaller. When approved by the purchaser, carbon steelmay be used for products of diameters larger than M12 through M20, inclusive.GAlloy steel shall be used. Steel is cons
24、idered to be alloy by the American Iron and Steel Institute when the maximum of the range given for the content of alloyingelements exceeds one or more of the following limits: manganese, 1.65 %; silicon, 0.60 %; copper, 0.60 %; or in which a definite range or a definite minimum quantity ofany of th
25、e following elements is specified or required within the limits of the recognized field of constructional alloy steels: aluminum, chromium up to 3.99 %, cobalt,columbium, molybdenum, nickel, titanium, tungsten, vanadium, zirconium, or any other alloying elements added to obtain a desired alloying ef
26、fect.TABLE 2 Chemical Composition Requirements for Classes 8.8.3 and 10.9.3Element Composition, %AABCDEFCarbon:Heat analysisProduct analysis0.330.400.310.420.380.480.360.500.150.250.140.260.150.250.140.260.200.250.180.270.200.250.190.26Manganese:Heat analysisProduct analysis0.901.200.861.240.700.900
27、.670.930.801.350.761.390.401.200.361.240.601.000.561.040.901.200.861.24Phosphorus:Heat analysisProduct analysis0.040 max0.045 max0.060.120.060.1250.035 max0.040 max0.040 max0.045 max0.040 max0.045 max0.040 max0.045 maxSulfur:Heat analysisProduct analysis0.050 max0.055 max0.050 max0.055 max0.040 max0
28、.045 max0.050 max0.055 max0.040 max0.045 max0.040 max0.045 maxSilicon:Heat analysisProduct analysis0.150.350.130.370.300.500.250.550.150.350.130.370.250.500.200.550.150.350.130.370.150.350.130.37Copper:Heat analysisProduct analysis0.250.450.220.480.200.400.170.430.200.500.170.530.300.500.270.530.300
29、.600.270.630.200.400.170.43Nickel:Heat analysisProduct analysis0.250.450.220.480.500.800.470.830.250.500.220.530.500.800.470.830.300.600.270.630.200.400.170.43Chromium:Heat analysisProduct analysis0.450.650.420.680.500.750.470.830.300.500.270.530.501.000.451.050.600.900.550.950.450.650.420.68Vanadiu
30、m:Heat analysisProduct analysis.0.020 min0.010 min.Molybdenum:Heat analysisProduct analysis.0.06 max0.07 max.0.10 max0.11 max.Titanium:Heat analysisProduct analysis.0.05 max.AA, B, C, D, E, and F are types of material used for Property Classes 8.8.3 and 10.9.3 bolts, screws, and studs. Selection of
31、a composition shall be at the option ofthe product manufacturer except that sizes M20 and larger shall conform to Composition A or B only.F568M042A 588/A 588M Specification for High-Strength Low-AlloyStructural Steel with 50 ksi 345 MPa Minimum YieldPoint to 4-in. 100-mm ThickA 751 Test Methods, Pra
32、ctices, and Terminology forChemical Analysis of Steel ProductsB 695 Specification for Coatings of Zinc MechanicallyDeposited on Iron and SteelD 3951 Practice for Commercial PackagingF 606 Test Methods for Determining the Mechanical Prop-erties of Externally and Internally Threaded Fasteners,Washers,
33、 and RivetsF 606M Test Methods for Determining the MechanicalProperties of Externally and Internally Threaded Fasteners,Washers, and Rivets MetricF 788/F 788M Specification for Surface Discontinuities ofBolts, Screws, and Studs, Inch and Metric SeriesF 1470 Guide for Fastener Sampling for Specified
34、Mechani-cal Properties and Performance RequirementsG 101 Guide for Estimating the Atmospheric CorrosionResistance of Low-Alloy Steels2.2 ISO Standard:3ISO 898-1, Mechanical Properties of Fasteners, Part I,Bolts, Screws, and Studs2.3 ASME Standards:3B 18.2.3.1M Metric Hex Cap ScrewsB 18.2.3.2M Metric
35、 Formed Hex ScrewsB 18.2.3.3M Metric Heavy Hex ScrewsB 18.2.3.4M Metric Hex Flange ScrewsB 18.2.3.5M Metric Hex BoltsB 18.2.3.6M Metric Heavy Hex BoltsB 18.5.2.1M Metric Round Head Short Square Neck BoltsB 18.5.2.2M Metric Round Head Square Neck Bolts3. Ordering Information3.1 Orders for products re
36、ferencing this specification shallinclude the following:3.1.1 Quantity (number of pieces),3.1.2 Name of product (that is, type and style of bolt, screw,or stud),3.1.3 Dimensions, including nominal thread diameter,thread pitch, and length (see Section 7),3.1.4 Property class,3.1.5 Zinc CoatingSpecify
37、 the zinc coating process re-quired, for example, hot dip, mechanically deposited, or nopreference (see 4.5),3.1.6 Other FinishesSpecify other protective finish, ifrequired,3.1.7 ASTM designation and year of issue, and3.1.8 Any special requirements (for example, mechanicalrequirements, see Tables 3
38、and 4, or proof load testing, seeTables 5 and 6; stud marking, see 15.2.3; additional testing, seeSection 9).3.1.9 Test reports if required, see Section 14.4. Materials and Manufacture4.1 Steel for bolts, screws, and studs shall be made by theopen-hearth, basic-oxygen, or electric-furnace process.4.
39、2 Heading Practice:4.2.1 Methods other than upsetting or extrusion, or both, arepermitted only by special agreement between purchaser andproducer.4.2.2 Class 4.6 may be hot or cold headed at the option ofthe manufacturer.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4t
40、h Floor, New York, NY 10036.TABLE 3 Mechanical Requirements for Bolts, Screws, and StudsPropertyClassNominalDiameter ofProductFull Size Bolts, Screws, and Studs Machined Test Specimens of Bolts, Screws,and StudsSurfaceHardnessProduct HardnessProof LoadATensileStrength,MPaAYieldStrength,MPaBTensileSt
41、rength,MPaElonga-tion, %ReductionofArea, %Rockwell30NRockwell VickersLengthMeasurementMethod,MPaYieldStrengthMethod,MPaMin Min Min Min Min Max Min Max Min Max4.6 M5M100 225 240 400 240C400 22 35 . . . B67 B95 120 2204.8 M1.6M16 310 340 420 340 420 14 35 . . . B71 B95 130 2205.8 M5M24D380 420 520 420
42、 520 10 35 . . . B82 B95 160 2208.8 M20M80 600 660 830 660 830 12 35 53 C23 C34 255 3368.8.3 M20M36 600 660 830 660 830 12 35 53 C23 C34 255 3369.8 M1.6M16 650 720 900 720 900 10 35 56 C27 C36 280 36010.9 M5M100 830 940 1040 940 1040 9 35 59 C33 C39 327 38210.9.3 M16M36 830 940 1040 940 1040 9 35 59
43、 C33 C39 327 38212.9EM1.6M100 970 1100 1220 1100 1220 8 35 63 C38 C44 372 434AProof load and tensile strength values for full size products of each property class are given in Table 5.BYield strength is stress at which a permanent set of 0.2 % of gage length occurs.CYield point shall apply instead o
44、f yield strength at 0.2 % offset for Class 4.6 products.DClass 5.8 applies only to bolts and screws with lengths 150 mm and shorter and to studs of all lengths.ECaution is advised when considering the use of Class 12.9 bolts, screws, and studs. Capability of the bolt manufacturer, as well as the ant
45、icipated in-use environment,should be considered. High-strength products of Class 12.9 require rigid control of heat-treating operations and careful monitoring of as-quenched hardness, surfacediscontinuities, depth of partial decarburization, and freedom from carburization. Some environments may cau
46、se stress corrosion cracking of nonplatedaswellaselectroplated products.F568M0434.2.3 Classes 4.8, 5.8, 8.8, 8.8.3, 9.8, 10.9, 10.9.3, and 12.9bolts and screws in nominal thread diameters up to M20inclusive with lengths up to ten times the nominal product sizeor 150 mm, whichever is shorter, shall b
47、e cold headed, exceptthat they may be hot headed by special agreement with thepurchaser. Larger diameters and longer lengths may be cold orhot headed at the option of the manufacturer.4.3 Threading Practice:4.3.1 Threads on Class 4.6 bolts and screws and on allclasses of studs may be cut, rolled, or
48、 ground at the option ofthe manufacturer.4.3.2 Threads on Classes 4.8, 5.8, 8.8, 8.8.3, 9.8, 10.9,10.9.3, and 12.9 bolts and screws in nominal thread diametersup to M20 inclusive, and product lengths up to 150 mminclusive, shall be roll threaded, except by special agreementwith the purchaser. Thread
49、s of these classes on bolts andscrews larger than M20 or longer than 150 mm or both, may berolled, cut, or ground at the option of the manufacturer.4.4 Heat Treatment:4.4.1 Class 4.6 bolts and screws and Classes 4.6, 4.8, and5.8 studs need not be heat treated.4.4.2 Classes 4.8 and 5.8 bolts and screws shall be stressrelieved if necessary to assure the soundness of the head toshank junction. When stress relieving is specified by thepurchaser, Class 5.8 bo
