ASTM_F_568M_-_02.pdf

Designation:F 568M 02METRICStandard 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 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.This standard has been approved for use by agencies of the Department of Defense.1.Scope*1.1 This specification covers chemical 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 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 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 tonegotiation 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 recognized 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.The atmospheric corrosion resistance of these steels issubstantially better than that of carbon steel with or withoutcopper addition.See 5.2.When properly exposed to theatmosphere,these steels can be used bare(uncoated)for manyapplications.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 supplied 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 mechanical 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:A 153 Specification for Zinc Coating(Hot-Dip)on Iron andSteel Hardware2A 307 Specification for Carbon Steel Bolts and Studs,60 000 psi Tensile Strength3A 325 Specification for Structural Bolts,Steel,HeatTreated,120/105 ksi Minimum Tensile Strength3A 325M Specification for High-Strength Bolts for Struc-tural Steel Joints Metric3A 354 Specification for Quenched and Tempered AlloySteel Bolts,Studs,and Other Externally Threaded Fasten-ers3A 449 Specification for Quenched and Tempered SteelBolts and Studs3A 490 Specification for Heat-Treated Steel Structural Bolts,150 ksi Minimum Tensile Strength3A 490M Specification for High-Strength Steel Bolts,Classes 10.9 and 10.9.3,for Structural Steel Joints Met-ric3A 574 Specification for Alloy Steel Socket-Head CapScrews3A 588/A588M Specification for High-Strength Low-Alloy1This specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subcommittee F16.02 on Steel Bolts,Nuts,Rivets and Washers.Current edition approved Oct.10,2002.Published November 2002.Originallypublished as F 568 79.Last previous edition F 568 98.2Annual Book of ASTM Standards,Vol 01.06.3Annual Book of ASTM Standards,Vol 01.08.1*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 19428-2959,United States.Structural Steel with 50 ksi 345 MPa Minimum YieldPoint to 4 in.100 mm Thick4A 751 Test Methods,Practices,and Terminology forChemical Analysis of Steel Products5B 695 Specification for Coatings of Zinc MechanicallyDeposited on Iron and Steel6D 3951 Practice for Commercial Packaging7F 606M Test Methods for Determining the MechanicalProperties of Externally and Internally Threaded Fasteners,Washers,and Rivets Metric3F 788/F788M Specification for Surface Discontinuities ofBolts,Screws,and Studs,Inch and Metric Series3F 1470 Guide for Fastener Sampling for Specified Mechani-cal Properties and Performance Requirements5G 101 Guide for Estimating the Atmospheric CorrosionResistance of L