1、Designation:F879M02a(Reapproved 2015)Standard Specification forStainless Steel Socket Button and Flat Countersunk HeadCap Screws(Metric)1This standard is issued under the fixed designation F879M;the number immediately following the designation indicates the year oforiginal adoption or,in the case of
2、 revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers the chemical and mechanicalrequirements for stainless steel metric hexagon
3、socket button(SBHCS)and flat countersunk(SFHCS)head cap screws withnominal thread M 3 through M 20 intended for use in applica-tions requiring general corrosion resistance.1.2 The following three property classes are covered:1.2.1 Austenitic Class A1-50 in an annealed condition at585 MPa maximum,1.2
4、.2 Austenitic Class A155 in a cold worked condition at550 MPa minimum,and1.2.3 Austenitic Class A1-70 in a cold-worked condition at700 MPa minimum.1.3 UnitsThe values stated in SI units are to be regardedas standard.No other units of measurement are included in thisstandard.1.4 The following hazard
5、caveat pertains only to Section 12,Test Methods:This standard does not purport to address all ofthe safety problems,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory
6、 limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2A262 Practices for Detecting Susceptibility to IntergranularAttack in Austenitic Stainless SteelsA342/A342M Test Methods for Permeability of WeaklyMagnetic MaterialsA380 Practice for Cleaning,Descaling,and Passivation ofStainless St
7、eel Parts,Equipment,and SystemsA555/A555M Specification for General Requirements forStainless Steel Wire and Wire RodsA751 Test Methods,Practices,and Terminology for Chemi-cal Analysis of Steel ProductsA967 Specification for Chemical Passivation Treatments forStainless Steel PartsD3951 Practice for
8、Commercial PackagingE18 Test Methods for Rockwell Hardness of Metallic Ma-terialsE92 Test Method for Vickers Hardness of Metallic Materials(Withdrawn 2010)3E384 Test Method for Knoop and Vickers Hardness ofMaterialsF606M Test Methods for Determining the Mechanical Prop-erties of Externally and Inter
9、nally Threaded Fasteners,Washers,and Rivets(Metric)F738M Specification for Stainless Steel Metric Bolts,Screws,and Studs(Withdrawn 2014)3F788/F788M Specification for Surface Discontinuities ofBolts,Screws,and Studs,Inch and Metric SeriesF1470 Practice for Fastener Sampling for Specified Me-chanical
10、Properties and Performance Inspection2.2 ASME Standards:B 18.3.4M Hexagon Socket Button Head Cap Screws(Met-ric Series)4B 18.3.5M Hexagon Socket Flat Countersunk Head CapScrews(Metric Series)43.Classification3.1 The designation of the property class and conditions ofthis specification shall be consi
11、stent with the stainless steeldesignations in Specification F738M.3.2 The austenitic stainless steel socket screw shall bedesignated F879M A1-50,F879M A155,or F879M A1-70.4.Ordering Information4.1 Orders for material under this specification shall includethe following information:1This specification
12、 is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subcommittee F16.04 on NonferrousFasteners.Current edition approved Sept.1,2015.Published November 2015.Originallyapproved in 1984.Last previous edition approved in 2008 as F879 02a(2008).DOI:10.1520/F08
13、79M-02AR15.2For 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 page onthe ASTM website.3The last approved version of this historical standard
14、is referenced onwww.astm.org.4Available from Global Engineering Documents,15 Inverness Way,EastEnglewood,CO 80112-5704,http:/.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.1.1 Quantity(number of pieces of each item).4.1.2 Name of the
15、screw,SBHCS or SFHCS.4.1.3 Dimensions,including nominal thread designation,thread pitch,and nominal screw length(millimetres).A stan-dard part number may be used for this definition.4.1.4 Property Class A1-50,A155,or A1-70.4.1.5 Certification,if required(see Section 15).4.1.6 ASTM specification and
16、year of issue.4.1.7 Any special or supplemental requirements(seeSupplementary Requirements S1 through S3).5.Materials and Manufacture5.1 Screws shall be formed by upsetting or extruding,orboth.5.2 Screws shall be roll threaded.5.3 Heat TreatmentAustenitic alloys Class A1-50 screws,following manufacture,shall be annealed by heating to 1040 630C to obtain maximum corrosion resistance and minimumpermeability.The screws shall be held for a sufficient time attemperature,then cooled at a rate sufficie
