1、Designation: F837M 16Standard Specification forStainless Steel Socket Head Cap Screws Metric1This standard is issued under the fixed designation F837M; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers the chemical and mechanicalrequirements for stainless steel metric socket head cap screws(SHCS) with nominal t
3、hread M1.6 through M36 and intendedfor use in applications requiring general corrosion resistance.1.2 Two groups of stainless steel alloys are covered, auste-nitic Grade A1 and martensitic Grade C1.1.3 Four property classes are covered: austenitic A1-50 inan annealed condition at 585 MPa maximum; au
4、steniticA155in a cold worked condition at 550 MPa minimum; austeniticA1-70 in a cold worked condition at 700 MPa minimum, andmartensitic C1-110 in a heat treated condition at 1100 MPaminimum.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included i
5、n thisstandard.1.5 This hazard statement pertains only to Section 13, TestMethods: This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and dete
6、rmine the applica-bility of regulatory 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/A380M Practice for Clea
7、ning, Descaling, and Passi-vation of Stainless Steel Parts, Equipment, and SystemsA751 Test Methods, Practices, and Terminology for Chemi-cal Analysis of Steel ProductsA967/A967M Specification for Chemical Passivation Treat-ments for Stainless Steel PartsD3951 Practice for Commercial PackagingE18 Te
8、st Methods for Rockwell Hardness of Metallic Ma-terialsE92 Test Methods for Vickers Hardness and Knoop Hard-ness of Metallic MaterialsE384 Test Method for Microindentation Hardness of Mate-rialsF606M Test Methods for Determining the Mechanical Prop-erties of Externally and Internally Threaded Fasten
9、ers,Washers, and Rivets (Metric)F738M Specification for Stainless Steel Metric Bolts,Screws, and Studs (Withdrawn 2014)3F1470 Practice for Fastener Sampling for Specified Me-chanical Properties and Performance Inspection2.2 ISO Standard:4ISO 4762 Hexagon socket head cap screws3. Classification3.1 Th
10、e designation of the property class for the twomaterials and conditions of this specification shall be consistentwith the stainless steel designations in Specification F738M.3.2 The austenitic stainless steel socket head cap screw shallbe designated F837MA1-50, F837MA1-55, or F837MA1-70.3.3 The mart
11、ensitic stainless steel socket head cap screwshall be designated F837M C1-110.4. Ordering Information4.1 Orders for socket head cap screws under this specifica-tion shall include:4.1.1 Quantity (number of pieces of each item),4.1.2 Name of the item (socket head cap screws, SHCS),4.1.3 Size (nominal
12、diameter, thread pitch, thread class,screw length) or part number,4.1.4 Property class (A1-50, A155, A1-70, or C1-110),1This specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subcommittee F16.04 on NonferrousFasteners.Current edition approv
13、ed May 1, 2016. Published July 2016. Originallypublished as F837M 83. Last previous edition approved in 2015 asF837M 02a(2015). DOI: 10.1520/F0837M-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStan
14、dards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from International Organization for Standardization (ISO), ISOCentral Secretariat, BIBC II, Chemin de Blandonnet 8,
15、 CP 401, 1214 Vernier,Geneva, Switzerland, http:/www.iso.org.*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 States14.1.5 ASTM specification and date of issue. When date ofissu
16、e is not specified, fasteners shall be furnished to the latestissue,4.1.6 Supplementary requirements, if any (see S1 throughS3),4.1.7 Additional special requirements, if any, to be specifiedon the purchase order:4.1.7.1 Forming (see 5.1),4.1.7.2 Threading (see 5.2),4.1.7.3 Surface finish (see 11.1),
17、4.1.7.4 Alloy selection (see 7.2),4.1.7.5 Test report (see 11.2),4.1.7.6 Additional testing (see section 12.3),4.1.7.7 Inspection (see 13.1),4.1.7.8 Rejection (see 14.1), and4.1.7.9 Certification (see 15.1).4.1.7.10 Special packaging requirements (see section18.1.2).5. Material and Manufacture5.1 Fo
18、rgingUnless otherwise specified, screws in sizesM3 through M20 with lengths up to 10 times the nominalproduct diameter or 150 mm, whichever is shorter, shall becold headed except that they may be hot headed or machinedby agreement with the purchaser. Larger sizes and lengths maybe cold or hot headed
19、. Screws smaller and larger than the M3through M36 range may be machined. Sockets may be forgedor machined at the option of the manufacturer.5.2 ThreadsUnless otherwise specified, screws in sizes upto M24 inclusive and product lengths up to 150 mm inclusiveshall have threads formed by rolling, excep
20、t by special agree-ment with the purchaser. Larger products may be rolled, cut, orground at the option of the manufacturer.6. Heat Treatment6.1 Austenitic alloys class A1-50 screws, followingmanufacture, shall be annealed by heating to 1040 6 30C toobtain maximum corrosion resistance and minimum per
21、me-ability. The screws shall be held for a sufficient time attemperature and then cooled at a rate sufficient to preventprecipitation of the carbide and to provide the propertiesspecified in Table 1.6.2 When Condition A1-55 or A1-70 is specified, theaustenitic alloys shall be annealed as specified i
22、n 6.1 generallyby the raw material manufacturer, then cold worked to developspecific properties.6.3 Martensitic alloy Class C1 110 screws shall be hardenedand tempered by heating to 1010 6 30C sufficient foraustenitization, holding for at least12 h, rapid air or oilquenching, reheating to 275C minim
23、um and holding for atleast 1 h and then air cooling to provide the properties specifiedin Table 1.7. Chemical Composition7.1 It is the intent of this specification that screws shall beordered by property class. The chemical composition of thescrew material shall conform to the requirements of Table
24、2.7.2 Unless otherwise specified in the inquiry and purchaseorder (see Supplementary Requirement S2) when A1-50,A1-55, orA1-70 property class is specified, the choice of alloyused by the manufacturer shall be clearly identified on allcertification required in the purchase order The chemicalcompositi
25、on shall conform to the limits specified in Table 2.7.3 When chemical analysis is performed by the purchaserusing finished fasteners representing each lot, the chemicalcontents obtained shall conform to the limits specified in Table2 for the specific alloy. Chemical contents shall conform to thetole
26、rances specified in Specification A751.7.3.1 In the event of discrepancy, a referee analysis asspecified in 13.1 of samples for each lot shall be made inaccordance with 12.3.1.1.8. Mechanical Properties8.1 Screws shall be tested in accordance with the mechani-cal testing requirements for the propert
27、y class, nominal threaddiameter, length, and specified minimum tensile strength asspecified in Table 3 and shall meet the mechanical require-ments specified for that product in Table 1.8.2 For products on which both hardness and tension testsare performed, acceptance based on tensile requirements sh
28、alltake precedence over low hardness readings (see Table 4).9. Corrosion Resistance9.1 Carbide Precipitation:TABLE 1 Mechanical Property RequirementsProperty ClassNominalThreadDiameterAFull Size Product Tests Machined Specimen Tests Core HardnessBTensile Strength,MPaMinimumExtensionCTensileStrength,
29、MPaYieldStrength,MPaElon-gation,%Vickers RockwellA150 M1.6 to M36 585 max 0.6D 585 max 380 max 40 210 max 95 HRB maxA1-55 M1.6 to M20 550 min 0.4D 550 min 270 min 25 160 min 50 HRA minA170 M1.6 to M20 700 min 0.4D 600 min 450 min 20 220 min 59 HRA minC1-110 M1.6 to M5 1100 . . . . . . . . . . . . 35
30、0440 3645 HRCM6 to M36 1100 0.2 D 1100 820 12 350440 3645 HRCAFor A155 and A170 property class fasteners with nominal thread diameter larger than M20, the mechanical properties shall be agreed upon between the user andmanufacturer.BCore hardness is only required when full-size product tensile testin
31、g cannot be accomplished.CD denotes nominal thread size.F837M 1629.1.1 Rod, bar, and wire in the austenitic alloy group A1(not including the free-machining grade 303) used to makefasteners in accordance with this specification shall be capableof passing the test for susceptibility to intergranular c
32、orrosionas specified in Practice E of Practices A262.9.1.2 As stated in Practices A262, samples may be subjectedto the faster and more severe screening test in accordance withPractice A. Failing Practice A, specimens shall be tested toPractice E and be considered satisfactory if passing Practice E.1
33、0. Dimensions10.1 Unless otherwise specified, the products shall conformto the requirements of ISO 4762 Hexagon socket head capscrews.11. Workmanship, Finish, and Appearance11.1 Surface TreatmentUnless otherwise specified, screwsshall be cleaned, descaled and passivated in accordance withPractice A3
34、80/A380M or Specification A967/A967M at theoption of the manufacturer.11.2 The surface discontinuities for these products shallconform to Specification F1470 and the additional limitationsspecified herein.11.2.1 Forging defects that connect the socket to the periph-ery of the head are not permissibl
35、e. Defects originating on theperiphery and with a traverse indicating a potential to intersectare not permissible. Other forging defects are permissibleprovided those located in the bearing area, fillet, and topsurfaces shall not have a depth exceeding 0.03 D or 0.13 m,whichever is greater. For peri
36、pheral discontinuities, the maxi-mum depth may be 0.06 D (see Fig. 1).11.2.2 Forging defects located in the socket wall within 0.1times the actual key engagement, T, from the bottom of thesocket are not permissible. Discontinuities located elsewhere inthe socket shall not have a length exceeding 0.2
37、5 T,oramaximum depth of 0.03 D not to exceed 0.13 mm (see Fig. 2).11.2.3 Seams in the shank shall not exceed a depth of 0.03D or 0.2 mm, whichever is greater.11.2.4 No transverse discontinuities shall be permitted inthe head-to-shank fillet area.11.2.5 Threads shall have no laps at the root or on th
38、e flanks,as shown in Fig. 3. Laps are permitted at the crests (Fig. 3c)that do not exceed 25 % of the basic thread depth, and on theflanks outside the pitch cylinder. Longitudinal seams rolledbeneath the root of the thread and across the crests of cutthreads are acceptable within the limits of 11.2.
39、3.12. Number of Tests12.1 The requirements of this specification shall be met incontinuous mass production for stock and the manufacturershall make sample inspections to ensure that the productconforms to the specified requirements. Additional tests ofindividual shipments of fasteners are not ordina
40、rily necessary.A record of the individual heat of steel in each lot shall bemaintained. The containers shall be coded to permit identifi-cation of the lot.TABLE 2 Chemical RequirementsPropertyClassUNSDesignation AlloyComposition, % maximum except as shownCarbon Manganese Phosphorus Sulfur Silicon Ch
41、romium Nickel Copper MolybdenumAustenitic AlloysA1 S30300 303A0.15 2.00 0.20 0.15 min 1.00 17.0 to 19.0 8.0 to 10.0 . . . 0.60 maxBA1 S30400 304 0.08 2.00 0.045 0.030 1.00 18.0 to 20.0 8.0 to 10.5 1.00 . . .A1 S30403 304L 0.030 2.00 0.045 0.030 1.00 18.0 to 20.0 8.0 to 12.0 1.00 . . .A1 S30500 305 0
42、.12 2.00 0.045 0.030 1.00 17.0 to 19.0 10.5 to 13.0 1.00 . . .A1 S38400 384 0.08 2.00 0.045 0.030 1.00 15.0 to 17.0 17.0 to 19.0 . . . . . .A1 S20300 XM1A0.08 5.0 to 6.5 0.040 0.18 to 0.35 1.00 16.0 to 18.0 5.0 to 6.5 1.75 to 2.25 0.50 maxBA1 S30430 189LW 0.10 2.00 0.045 0.030 1.00 17.0 to 19.0 8.0
43、to 10.0 3.00 to 4.00 . . .A1 S30433 302HQ 0.03 2.00 0.045 0.030 1.00 17.0 to 19.0 8.0 to 10.0 3.0 to 4.0 . . .A1 S31600 316 0.08 2.00 0.045 0.030 1.00 16.0 to 18.0 10.0 to 14.0 . . . 2.0 to 3.0A1 S31603 316L 0.03 2.00 0.045 0.030 1.00 16.0 to 18.0 10.0 to 14.0 . . . 2.0 to 3.0Martensitic AlloysC1 S4
44、100 410 0.15 1.00 0.040 0.030 1.00 11.5 to 13.5 . . . . . . . . .AFree machining grades are not recommended for forged product. These grades may be furnished only when approved by the purchaser.BAt manufacturers option, determined only when intentionally added.TABLE 3 Mechanical Testing Requirements
45、Item Product LengthHardnessTest conducted Using Full SizeProductTest Conducted Using Machined Test Specificationmax minExten-sionAxial TensileStrengthYield Strength0.2 % offsetTensileStrengthElonga-tion1 #3 DABB. . . . .23D to 300 mmB.BB. . .3 Over 300 mmB. A A B B BAD denotes nominal diameter of pr
46、oduct.BDenotes mandatory test. In addition, either all tests denoted by A or all tests denoted by B shall be performed. In case of arbitration, full-size tests, denoted A, shall bedecisive.F837M 16312.2 When specified in the purchase order, the manufacturershall furnish a test report of the last com
47、plete set of chemicalanalysis and mechanical tests for each stock size in eachshipment.12.3 When tests of individual shipments are required,Supplementary Requirement S1 must be specified in theinquiry and order.12.3.1 When the purchaser does not specify the samplingplan and basis of acceptance, the
48、following shall apply:12.3.1.1 The lot, for purposes of selecting samples, shallconsist of all products offered for inspection and testing, at onetime, that are the same type, style, nominal diameter, threadpitch, nominal length, material (alloy), property class, andsurface finish.12.3.1.2 From each
49、 lot, samples shall be selected at randomand tested for each requirement in accordance with thefollowing plan:Number of Pieces in LotNumber ofSamples800 and less 1Over 800 to 8000, incl 2Over 8000 to 22 000, incl 3Over 22 000 512.3.1.3 Should any sample fail to meet the requirements ofa specified test, double the number of samples from the samelot shall be retested for the requirement(s) in which it failed.All of the additional samples shall conform to the specificationor the lot shall be rejected.12.3.1.4 If the failure of a test specimen is due to imprope
