1、Designation: F 837M 02aMETRICStandard Specification forStainless Steel Socket Head Cap Screws Metric1This standard is issued under the fixed designation F 837M; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. 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. Scope1.1 This specification covers the chemical and mec
3、hanicalrequirements for stainless steel metric socket head cap screws(SHCS) with nominal thread 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 pro
4、perty classes are covered: austenitic A1-50 inan annealed condition at 585 MPa maximum; austenitic A155in 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 This hazard st
5、atement 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 determine the applica-bility of regul
6、atory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:A 262 Practices for Detecting Susceptibility to Intergranu-lar Attack in Austenitic Stainless Steels2A 342 Test Methods for Permeability of Feebly MagneticMaterials3A 380 Practices for Cleaning, Descaling, and Passivation ofSta
7、inless Steel Parts, Equipment, and Systems2A 555/A555M Specification for General Requirements forStainless Steel Wire and Wire Rods2A 751 Test Methods, Practices, and Terminology forChemical Analysis of Steel Products2A 967 Specification for Chemical Passivation Treatmentsfor Stainless Steel Parts2D
8、 3951 Practice for Commercial Packaging4E18 Test Methods for Rockwell Hardness and RockwellSuperficial Hardness of Metallic Materials5E92 Test Method for Vickers Hardness of Metallic Mate-rials5E 384 Test Method for Microhardness of Materials5F 606M Test Methods for Determining the MechanicalPropert
9、ies of Externally and Internally Threaded Fasteners,Washers, and Rivets Metric6F 738M Specification for Stainless Steel Metric Bolts,Screws, and Studs6F 788/F788M Specification for Surface Discontinuities ofBolts, Screws, and Studs, Inch and Metric Series6F 1470 Guide for Fastener Sampling for Speci
10、fied Mechani-cal Properties and Performance Inspection62.2 ASME Standard:ASME B 18.3.1M Socket Head Cap Screws (Metric Se-ries)73. Classification3.1 The designation of the property class for the twomaterials and conditions of this specification shall be consistentwith the stainless steel designation
11、s in Specification F 738M.3.2 The austenitic stainless steel socket head cap screw shallbe designated F837MA1-50, F837MA1-55, or F 837MA1-70.3.3 The martensitic stainless steel socket head cap screwshall be designated F837M C1-110.4. Ordering Information4.1 Orders for socket head cap screws under th
12、is specifica-tion shall include:4.1.1 Quantity (number of pieces of each item),1This specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subcommittee F16.04 on NonferrousFasteners.Current edition approved July 10, 2002. Published September 20
13、02. Originallypublished as F 837M 83. Last previous edition F 837M 02.2Annual Book of ASTM Standards, Vol 01.03.3Annual Book of ASTM Standards, Vol 03.04.4Annual Book of ASTM Standards, Vol 15.09.5Annual Book of ASTM Standards, Vol 03.01.6Annual Book of ASTM Standards, Vol 01.08.7Available from Glob
14、al Engineering Documents, 15 Inverness Way, Englewood,CO 80112.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.1.2 Name of the item (socket head cap screws, SHCS),4.1.3 Size (nominal diameter, thread pitch, thread class,screw lengt
15、h) or part number,4.1.4 Property class (A1-50, A155, A1-70, or C1-110),4.1.5 ASTM specification and date of issue. When date ofissue 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
16、 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),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)
17、, and4.1.7.9 Certification (see 15.1).4.1.7.10 Special packaging requirements (see section18.1.2).5. Material and Manufacture5.1 ForgingUnless otherwise specified, screws in sizesM3 through M20 with lengths up to 10 times the nominalproduct diameter or 150 mm, whichever is shorter, shall becold head
18、ed except that they may be hot headed or machinedby agreement with the purchaser. Larger sizes and lengths maybe cold or hot headed. 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
19、specified, screws in sizes upto M24 inclusive and product lengths up to 150 mm inclusiveshall have threads formed by rolling, except 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 A
20、1-50 screws, following manu-facture, shall be annealed by heating to 1040 6 30C to obtainmaximum corrosion resistance and minimum permeability.The screws shall be held for a sufficient time at temperatureand then cooled at a rate sufficient to prevent precipitation ofthe carbide and to provide the p
21、roperties specified in Table 1.6.2 When Condition A1-55 or A1-70 is specified, theaustenitic alloys shall be annealed as specified in 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
22、by heating to 1010 6 30C sufficient foraustenitization, holding for at least12 h, rapid air or oilquenching, reheating to 275C minimum 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
23、 screws shall beordered by property class. The chemical composition of thescrew material shall conform to the requirements of Table 2.7.2 Unless otherwise specified in the inquiry and purchaseorder (see Supplementary Requirement S2) when A1-50,A1-55, or A1-70 property class is specified, the choice
24、of alloyused by the manufacturer shall be clearly identified on allcertification required in the purchase order The chemicalcomposition 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 chemica
25、lcontents obtained shall conform to the limits specified in Table2 for the specific alloy. Chemical contents shall conform to thetolerances specified in Specification A 555/A 555M.7.3.1 In the event of discrepancy, a referee analysis asspecified in 13.1 of samples for each lot shall be made inaccord
26、ance with 12.3.1.1.8. Mechanical Properties8.1 Screws shall be tested in accordance with the mechani-cal testing requirements for the property class, nominal threaddiameter, length, and specified minimum tensile strength asspecified in Table 3 and shall meet the mechanical require-ments specified fo
27、r that product in Table 1.8.2 For products on which both hardness and tension testsare performed, acceptance based on tensile requirements shalltake precedence over low hardness readings (see Table 4).9. Corrosion Resistance9.1 Carbide Precipitation:9.1.1 Rod, bar, and wire in the austenitic alloy g
28、roup A1(not including the free-machining grade 303) used to makeTABLE 1 Mechanical Property RequirementsProperty ClassNominalThreadDiameterAFull Size Product Tests Machined Specimen Tests Core HardnessBTensile Strength,MPaMinimumExtensionCTensileStrength,MPaYieldStrength,MPaElon-gation,%Vickers Rock
29、wellA150 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 . . . . . . . . . . . . 350440 3645 HRCM6 to M36 1100 0.2D 1100 820 12
30、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 testing cannot be accomplished.CD denotes nominal th
31、read size.F 837M 02a2fasteners in accordance with this specification shall be capableof passing the test for susceptibility to intergranular corrosionas specified in Practice E of Practices A 262.9.1.2 As stated in Practices A 262, samples may be sub-jected to the faster and more severe screening te
32、st in accor-dance with Practice A. Failing Practice A, specimens shall betested to Practice E and be considered satisfactory if passingPractice E.10. Dimensions10.1 Unless otherwise specified, the products shall conformto the requirements ofASME B18.3.1M Hexagon Socket HeadCap Screws (Metric Series)
33、.11. Workmanship, Finish, and Appearance11.1 Surface TreatmentUnless otherwise specified,screws shall be cleaned, descaled and passivated in accordancewith Practice A 380 or Specification A 967 at the option of themanufacturer.11.2 The surface discontinuities for these products shallconform to Speci
34、fication F 788/F 788M and the additionallimitations specified herein.11.2.1 Forging defects that connect the socket to the periph-ery of the head are not permissible. Defects originating on theperiphery and with a traverse indicating a potential to intersectare not permissible. Other forging defects
35、 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 peripheral discontinuities, the maxi-mum depth may be 0.06 D (see Fig. 1).TABLE 2 Chemical RequirementsPropertyClassUNSDesignationAlloyCompo
36、sition, % maximum except as shownCarbon Manganese Phosphorus Sulfur Silicon Chromium 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
37、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 0.12 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
38、 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 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 0.04
39、5 0.030 1.00 16.0 to 18.0 10.0 to 14.0 . . . 2.0 to 3.0Martensitic AlloysC1 S4100 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, de
40、termined only when intentionally added.TABLE 3 Mechanical Testing RequirementsItem Product LengthHardnessTest conducted Using Full SizeProductTest Conducted Using Machined Test Specificationmax minExten-sionAxial TensileStrengthYield Strength0.2 % offsetTensileStrengthElonga-tion1 #3 DABB. . . . .23
41、D to 300 mmB.BB. . .3 Over 300 mmB. A A B B BAD denotes nominal diameter of product.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, shallbe decisive.TABLE 4 Tensile Strength Values f
42、or Full Size Fasteners, kNNominal Sizeand ThreadPitchStressArea,mm2 AProperty ClassesA1-50 A1-55 A1-70 C1-110TensileStrength,kNBTensileStrength,kNCTensileStrength,kNDTensileStrength,kNEM1.6 3 0.35 1.27 0.74 0.70 0.89 1.40M2 3 0.4 2.07 1.21 1.14 1.45 2.28M2.5 3 0.45 3.39 1.98 1.87 2.37 3.73M3 3 0.5 5
43、.03 2.94 2.77 3.52 5.53M3.5 3 0.6 6.78 3.97 3.73 4.75 7.46M4 3 0.7 8.78 5.14 4.83 6.15 9.66M5 3 0.8 14.2 8.30 7.80 9.93 15.6M6 3 1 20.1 11.8 11.1 14.1 22.1M8 3 1.25 36.6 21.4 20.1 25.6 40.3M10 3 1.5 58.0 33.9 31.9 40.6 63.8M12 3 1.75 84.3 49.3 46.3 59.0 92.7M14 3 2 115 67.5 63.5 80.8 126.5M16 3 2 15
44、7 91.7 86.2 110 173M20 3 2.5 245 143 135 171 270M24 3 3 353 206 . . . . . . 388M30 3 3.5 561 328 . . . . . . 617M36 3 4 817 478 . . . . . . 899AStress Area = 0.7854 ( D - 0.9382P)2where:D = nominal thread diameter, mm, andP = thread pitch, mm.BTensile based on stress area and 585 MPa maximum.CTensil
45、e based on stress area and 550 MPa minimum through M20DTensile based on stress area and 700 MPa minimum through M20.ETensile based on stress area and 1100 MPa minimum.F 837M 02a311.2.2 Forging defects located in the socket wall within 0.1times the actual key engagement, T, from the bottom of thesock
46、et are not permissible. Discontinuities located elsewhere inthe socket shall not have a length exceeding 0.25 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 discontinuiti
47、es shall be permitted inthe head-to-shank fillet area.11.2.5 Threads shall have no laps at the root or on the 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 rolled
48、beneath the root of the thread and across the crests of cutthreads are acceptable within the limits of 11.2.3.12. 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 produc
49、tconforms to the specified requirements. Additional tests ofindividual shipments of fasteners are not ordinarily 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.12.2 When specified in the purchase order, the manufacturershall furnish a test report of the last complete 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
