Designation: A 325 – 00
 American AssociationState Highway andTransportation OfficialsStandard AASHTO No.: M 164
Standard Specification for
Structural Bolts, Steel, Heat Treated, 120/105 ksi MinimumTensile Strength
1
This standard is issued under the fixed designation A 325; the number immediately following the designation indicates the year of srcinal 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
2
covers two types of quenched andtempered steel structural bolts having a minimum tensilestrength of 120 ksi for sizes 1.0 in. and less and 105 ksi forsizes over 1.0 to 1
1
 ⁄ 
2
 in., inclusive.1.2 The bolts are intended for use in structural connections.These connections are covered under the requirements of theSpecification for Structural Joints UsingASTMA 325 orA 490Bolts, approved by the Research Council on Structural Con-nections of the Engineering Foundation.
3
1.3 The bolts are furnished in sizes
 1
 ⁄ 
2
 to 1
1
 ⁄ 
2
 in., inclusive.They are designated by type, denoting chemical composition asfollows:
Type DescriptionType 1 Medium carbon, carbon boron, or medium carbon alloy steel.Type 2 Withdrawn in November 1991.Type 3 Weathering steel. Atmospheric corrosion resistance and weath-ering characteristics are comparable to that of steels in Specifi-cations A 242/A 242M, A 588/A 588M, and A 709/A 709M. Theatmospheric corrosion resistance of these steels is substantiallybetter than that of carbon steel with or without copper addition(see 5.2). When properly exposed to the atmosphere, thesesteels can be used bare (uncoated) for many applications.
N
OTE
 1—Bolts for general applications, including anchor bolts, arecovered by Specification A 449. Also refer to Specification A 449 forquenched and tempered steel bolts and studs with diameters greater than1
1
 ⁄ 
2
 in., but with similar mechanical properties.N
OTE
 2—A complete metric companion to Specification A 325 hasbeen developed—Specification A 325M; therefore no metric equivalentsare presented in this specification.
1.4 The following safety hazards caveat pertains only tothe test methods portion, Section 10, of this specification:
 Thisstandard does not purport to address all of the safety concerns,if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limita-tions prior to use.
2. Referenced Documents
2.1
 ASTM Standards:
A 153 Specification for Zinc Coating (Hot-Dip) on Iron andSteel Hardware
4
A 194/A 194M Specification for Carbon and Alloy SteelNuts for Bolts for High-Pressure and High-TemperatureService
5
A 242/A 242M Specification for High-Strength Low-AlloyStructural Steel
6
A 449 Specification for Quenched and Tempered SteelBolts and Studs
7
A 490 Specification for Heat-Treated Steel Structural Bolts,150 ksi Minimum Tensile Strength
7
A 563 Specification for Carbon and Alloy Steel Nuts
7
A 588/A 588M Specification for High-Strength Low-AlloyStructural Steel with 50 ksi [345 MPa] Minimum YieldPoint to 4 in. [100 mm] Thick 
6
A 709/A 709M Specification for Carbon and High-Strength Low-Alloy Structural Steel Shapes, Plates, andBars and Quenched-and-Tempered Alloy Structural SteelPlates for Bridges
6
A 751 Test Methods, Practices, and Terminology forChemical Analysis of Steel Products
8
B 695 Specification for Coatings of Zinc MechanicallyDeposited on Iron and Steel
9
D 3951 Practice for Commercial Packaging
10
F 436 Specification for Hardened Steel Washers
7
F 606 Test Methods for Determining the Mechanical Prop-erties of Externally and Internally Threaded Fasteners,Washers, and Rivets
7
F 788/F 788M Specification for Surface Discontinuities of 
1
This 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 July 10, 2000. Published September 2000. Originallypublished as A 325 – 64. Last previous edition A 325 – 97.
2
For
 ASME Boiler and Pressure Vessel Code
 applications see related Specifi-cation SA-325 in Section II of that Code.
3
Published by American Institute of Steel Construction, Wrigley Building, 400N. Michigan Ave., Chicago, IL 60611.
4
 Annual Book of ASTM Standards,
 Vol 01.06.
5
 Annual Book of ASTM Standards,
 Vol 01.01.
6
 Annual Book of ASTM Standards,
 Vol 01.04.
7
 Annual Book of ASTM Standards,
 Vol 01.08.
8
 Annual Book of ASTM Standards,
 Vol 01.03.
9
 Annual Book of ASTM Standards,
 Vol 02.05.
10
 Annual Book of ASTM Standards
, Vol 15.09.
1
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
COPYRIGHT merican Society for Testing and MaterialsLicensed by Information Handling Services
COPYRIGHT American Society for Testing and MaterialsLicensed by Information Handling Services
 
Bolts, Screws, and Studs, Inch and Metric Series
7
F 959 Specification for Compressible-Washer-Type DirectTension Indicators for Use with Structural Fasteners
7
G 101 Guide for Estimating the Atmospheric CorrosionResistance of Low-Alloy Steels
11
2.2
 ANSI/ASME Standards:
12
B 1.1 Unified Screw ThreadsB 18.2.1 Square and Hex Bolts and ScrewsB 18.18.3M Inspection and Quality Assurance for SpecialPurpose Fasteners2.3
 Military Standard:
13
MIL-STD-105 Sampling Procedure and Tables for Inspec-tion by Attributes
3. Ordering Information
3.1 Orders for bolts under this specification shall include thefollowing:3.1.1 Quantity (number of pieces of bolts and accessories).3.1.2 Size, including nominal bolt diameter and length (see3.1.3.1).3.1.2.1 Bolts threaded full length, specify SupplementaryRequirements S1.3.1.3 Name of product.3.1.3.1 Heavy Hex Structural Bolts are supplied unlessotherwise specified. For bolts other than Heavy Hex Structural,dimensional requirements must be specified on the purchaseinquiry and order. The thread length may not be changedexcept as provided in Supplementary Requirements S1.3.1.4 Type of bolt, that is, Type 1 or 3.3.1.5 ASTM designation and year of issue.3.1.6 Other components such as nuts, washers, and washertype direct tension indicators, if required.3.1.6.1 When such other components are specified to befurnished, also state “Nuts, washers, and direct tension indica-tors, or combination thereof, shall be furnished by lot number”.3.1.7 Accessories such as nuts and washers, when required.3.1.8
 Zinc Coating
—Specify the zinc coating process re-quired, for example, hot dip, mechanically deposited, or nopreference (see 4.3).3.1.9
 Other Finishes
—Specify other protective finish, if required.3.1.10 Test reports, if required (see Section 14).3.1.11 Special requirements.
N
OTE
 3—A typical ordering description follows: 1000 pieces 1 in. dia
3
 4 in. long Heavy Hex Structural Bolt,
 Type 1 ASTM A 325-XX 
; eachwith one Hardened Washer,ASTM F 436 Type 1; and one Heavy Hex Nut,ASTM A 563 Grade DH. Each component hot dip zinc coated. Nutslubricated.
3.2
 Recommended Nuts
:3.2.1 Unless otherwise specified, all nuts used on these boltsshall conform to the requirements of Specifications A 194/ A 194M or A 563, shall be heavy hex, and shall be of the classand surface finish for each type of bolt as follows:
11
 Annual Book of ASTM Standards
, Vol 03.02.
12
Available from American National Standards Institute, 11 West 42nd Street,13th Floor, New York, NY 10036.
13
Available from Standardization Documents Order Desk, Bldg. 4 Section D,700 Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
A 325
2
COPYRIGHT merican Society for Testing and MaterialsLicensed by Information Handling Services
COPYRIGHT American Society for Testing and MaterialsLicensed by Information Handling Services
 
Bolt Type and Finish Nut Class and Finish1, plain (noncoated) A 563-C, c 3, D, DH, DH3,plainA 194-2, 2H, plain1, zinc coated A 563-DH, zinc coatedA 194-2H, zinc coated (see3.2.2)3, plain A 563-C3, DH3, plain
3.2.2 When SpecificationA 194/A 194M Gr. 2H zinc coatednuts are supplied, the zinc coating, overtapping, lubrication,and rotational capacity testing shall be in accordance withSpecification A 563.3.3 Unless otherwise specified, all washers used on thesebolts shall conform to the requirements of Specifications F 436or F 959 and shall be of a surface finish for each type of boltas follows:
Bolt Type and Finish Washer Finish1, plain (uncoated) plain (uncoated)1, zinc coated zinc coated3, plain weathering steel, plain
4. Materials and Manufacture
4.1
 Heat Treatment 
—Bolts shall be heat treated by quench-ing in a liquid medium from above the austenitizing tempera-ture and then tempering by reheating to a temperature of atleast 800°F.4.2
 Threading
—Threads of bolts may be cut or rolled.4.3
 Zinc Coatings, Hot-dip and Mechanically Deposited 
:4.3.1 When zinc-coated fasteners are required, the pur-chaser shall specify the zinc coating process, for example, hotdip, mechanically deposited, or no preference.4.3.2 When hot-dip is specified, the fasteners shall bezinc-coated by the hot-dip process and the coating shallconform to the coating weight/thickness and performancerequirements of Class C of Specification A 153.4.3.3 When mechanically deposited is specified, the fasten-ers shall be zinc-coated by the mechanical deposition processand the coating shall conform to the coating weight/thicknessand performance requirements of Class 50 of SpecificationB 695.4.3.4 When no preference is specified, the supplier mayfurnish either a hot-dip zinc coating in accordance withSpecification A 153, Class C, or a mechanically deposited zinccoating in accordance with Specification B 695, Class 50.Threaded components (bolts and nuts) shall be coated by thesame zinc-coating process and the supplier’s option is limitedto one process per item with no mixed processes in a lot.4.4
 Lubrication
—When zinc coated nuts are ordered withthe bolts, the nuts shall be lubricated in accordance withSpecification A 563, Supplementary Requirement S1, to mini-mize galling.4.5
 Secondary Processing
—If heat treatment, zinc coating,lubrication, or other processing affecting properties is per-formed by a subcontractor, the fasteners shall be inspected aftersuch processing by the party responsible for supplying thefasteners to the user or installer. Heat treated fasteners shall betested for all mechanical properties; hot dip zinc coatedfasteners for all mechanical properties and rotational capacity;mechanically zinc coated fasteners for rotational capacity; andlubricated fasteners for rotational capacity.
5. Chemical Composition
5.1 Type 1 bolts shall be plain carbon steel, carbon/boronsteel, or alloy steel, at the manufacturers option, conforming tothe chemical composition specified in Table 1.5.2 Type 3 bolts shall be weathering steel and shall conformto one of the chemical compositions specified in Table 2. Theselection of the chemical composition,A, B, C, D, E, or F, shallbe at the option of the bolt manufacturer. See Guide G 101 formethods of estimating the atmospheric corrosion resistance of low alloy steels.5.3 Product analyses may be made by the purchaser fromfinished material representing each lot of bolts. The chemicalcomposition thus determined shall conform to the requirementsspecified in 5.1 or 5.2.5.4 Heats of steel to which bismuth, selenium, tellurium, orlead has been intentionally added shall not be permitted forbolts.5.5 For Type 1 bolts made from plain carbon steel or alloysteel, heats of steel to which boron has been intentionally
TABLE 1 Chemical Requirements for Type 1 Bolts
ElementCarbon SteelHeatAnalysisProductAnalysisCarbon 0.300.52 0.280.55Manganese, min 0.60 0.57Phosphorus, max 0.040 0.048Sulfur, max 0.050 0.058Silicon 0.150.30 0.130.32Boron see 5.5 and 5.6ElementCarbon Boron SteelHeatAnalysisProductAnalysisCarbon 0.300.52 0.280.55Manganese, min 0.60 0.57Phosphorus, max 0.040 0.048Sulfur, max 0.050 0.058Silicon 0.100.30 0.080.32Boron 0.00050.003 0.00050.003ElementAlloy SteelHeatAnalysisProductAnalysisCarbon 0.300.52 0.280.55Manganese, min 0.60 0.57Phosphorus, max 0.035 0.040Sulfur, max 0.040 0.045Silicon 0.150.35 0.130.37Boron see 5.5 and 5.6Alloying Elements
 A AA
Steel, as defined by theAmerican Iron and Steel Institute, shall be consideredto be alloy 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 quantityof any of the following elements is specified or required within the limits of therecognized 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 effect.
A 325
3
COPYRIGHT merican Society for Testing and MaterialsLicensed by Information Handling Services
COPYRIGHT American Society for Testing and MaterialsLicensed by Information Handling Services
 
added shall not be permitted.5.6 Compliance with 5.4 and 5.5 shall be based on certifi-cation that heats of steel having any of the listed elementsintentionally added were not used to produce the bolts.5.7 Chemical analyses shall be performed in accordancewith Test Methods, Practices, and Terminology A 751.
6. Mechanical Properties
6.1
 Hardness
—The bolts shall conform to the hardnessspecified in Table 3.6.2
 Tensile Properties
:6.2.1 Bolts having a length of 3 times the diameter or longer(see 6.2.3) shall be tested full size and shall conform to thetensile strength and proof load or alternative proof loadspecified in Table 4.6.2.2 Bolts having a length less than 3 times the diameterare not subject to tensile tests, except as permitted in 6.2.3.6.2.3 Bolts having a length of 2 times the diameter or longermay be tested full size for tensile properties whenever testequipment is available. In such cases reference to “3 times thediameter” in Table 3, 6.2.1, and 6.2.2 shall be considered to be“2 times the diameter”.6.2.4 For bolts on which hardness and tension tests areperformed, acceptance based on tensile requirements shall takeprecedence in the event of controversy over low hardness tests.6.3
 Rotational Capacity Test:
TABLE 2 Chemical Requirements for Type 3 Bolts
Element Composition, %Type 3 Bolts
A
A B C D E FCarbon:Heat analysisProduct analysis0.33–0.400.31–0.420.38–0.480.36–0.500.15–0.250.14–0.260.15–0.250.14–0.260.20–0.250.18–0.270.20–0.250.19–0.26Manganese:Heat analysisProduct analysis0.90–1.200.86–1.240.70–0.900.67–0.930.80–1.350.76–1.390.40–1.200.36–1.240.60–1.000.56–1.040.90–1.200.86–1.24Phosphorus:Heat analysisProduct analysis0.040 max0.045 max0.06–0.120.06–0.1250.035 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 max0.045 max0.050 max0.055 max0.040 max0.045 max0.040 max0.045 maxSilicon:Heat analysisProduct analysis0.15–0.350.13–0.370.30–0.500.25–0.550.15–0.350.13–0.370.25–0.500.20–0.550.15–0.350.13–0.370.15–0.350.13–0.37Copper:Heat analysisProduct analysis0.25–0.450.22–0.480.20–0.400.17–0.430.20–0.500.17–0.530.30–0.500.27–0.530.30–0.600.27–0.630.20–0.400.17–0.43Nickel:Heat analysisProduct analysis0.25–0.450.22–0.480.50–0.800.47–0.830.25–0.500.22–0.530.50–0.800.47–0.830.30–0.600.27–0.630.20–0.400.17–0.43Chromium:Heat analysisProduct analysis0.45–0.650.42–0.680.50–0.750.47–0.830.30–0.500.27–0.530.50–1.000.45–1.050.60–0.900.55–0.950.45–0.650.42–0.68Vanadium: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...............
A
A, B, C, D, E, and F are classes of material used for Type 3 bolts. Selection of a class shall be at the option of the bolt manufacturer.
TABLE 3 Hardness Requirements for Bolts
Bolt Size, in. Bolt Length,in.Brinell Rockwell CMin Max Min Max
1
 ⁄ 
2
 to 1, incl Less than3D
A
253 319 25 343D andover – 319 341
1
 ⁄ 
8
 to 1
1
 ⁄ 
2
,inclLess than3D
A
223 286 19 303D andover – 286 30
A
Bolts having a length less than 3 times the diameter are subject only tominimum/maximum hardness. Such lengths cannot be reasonably tensile tested.D = Nominal diameter or thread size.
A 325
4
COPYRIGHT merican Society for Testing and MaterialsLicensed by Information Handling Services
COPYRIGHT American Society for Testing and MaterialsLicensed by Information Handling Services
of 8