ASTM F593-22

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F593 − 17 F593 − 22
Standard Specification for
Stainless Steel Bolts, Hex Cap Screws, and Studs
This standard is issued under the fixed designation F593; the number immediately following the designation indicates the year of original
adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This specification covers the requirements for stainless steel bolts, hex cap screws, and studs 0.25 to 1.50 in., inclusive, in
nominal diameter in a number of alloys in common use and intended for service applications requiring general corrosion resistance.
1.2 Seven groups of stainless steel alloys are covered, including fourteen austenitic, two ferritic, four martensitic, and one
precipitation hardening.
A B
Group Alloys Condition
C
1 304, 305, 384, 304 L, (CW) cold worked
D
18-9LW, 302HQ, 304J3
C
2 316, 316 L (CW) cold worked
C
3 321, 347 (CW) cold worked
E C
4 430 (CW) cold worked
F
5 410 (H) hardened and tempered
6 431 (H) hardened and tempered
7 630 (AH) age hardened
A
Unless otherwise specified on the inquiry and order, the choice of an alloy from within a group shall be at the discretion of the fastener manufacturer (see 6.1).
B
See 4.2 for options.
C
Sizes 0.75 in. and larger may be hot worked and solution annealed, provided the bolts comply with the cold worked (CW) mechanical property requirements.
D
When approved by the purchaser, Alloys 303, 303Se, or XM1 may be furnished.
E
When approved by the purchaser, Alloy 430F may be furnished.
F
When approved by the purchaser, Alloys 416 or 416Se may be furnished.
1.3 Supplementary requirements of an optional nature are provided, applicable only when agreed upon between the manufacturer
and the purchaser at the time of the inquiry and order.
1.4 Suitable nuts for use with bolts, hex cap screws, and studs included in this specification are covered by Specification F594.
Unless otherwise specified, all nuts used on these fasteners shall conform to the requirements of Specification F594, shall be of
the same alloy group, and shall have a specified minimum proof stress equal to or greater than the specified minimum full-size
tensile strength of the externally threaded fastener.
1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
This specification is under the jurisdiction of ASTM Committee F16 on Fasteners and is the direct responsibility of Subcommittee F16.04 on Nonferrous Fasteners.
Current edition approved June 1, 2017Nov. 1, 2022. Published June 2017January 2023. Originally approved in 1978. Last previous edition approved in 20132017 as
ɛ1
F593 – 13aF593 – 17. . DOI: 10.1520/F0593-17.10.1520/F0593-22.
*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
F593 − 22
1.6 This standard 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels
A276 Specification for Stainless Steel Bars and Shapes
A342/A342M Test Methods for Permeability of Weakly Magnetic Materials
A380 Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems
A484/A484M Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
A493 Specification for Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging
A555/A555M Specification for General Requirements for Stainless Steel Wire and Wire Rods
A564/A564M Specification for Hot-Rolled and Cold-Finished Age-Hardening Stainless Steel Bars and Shapes
A582/A582M Specification for Free-Machining Stainless Steel Bars
A751 Test Methods and Practices for Chemical Analysis of Steel Products
A967 Specification for Chemical Passivation Treatments for Stainless Steel Parts
D3951 Practice for Commercial Packaging
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
F594 Specification for Stainless Steel Nuts
F606/F606M Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners,
Washers, Direct Tension Indicators, and Rivets
F1470 Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection
2.2 ASME Standards:
B1.1 Unified Inch Screw Threads
B18.2.1 Square and Hex Bolts and Screws, Including Hex Cap Screws
2.3 JIS Standard:
JIS G4309 Stainless Steel Wires
3. Ordering Information
3.1 Orders for bolts, hex cap screws, and studs under this specification shall include the following:
3.1.1 Quantity (number of pieces of each item and size),
3.1.2 Name of item (bolt, hex cap screw, stud, etc.),
3.1.3 Size (nominal diameter, threads per inch, length; see Section 9),
3.1.4 Alloy group number (see 6.1), and
3.1.5 Condition (see 4.2).
3.2 Orders for bolts, hex cap screws, and studs under this specification may include the following optional requirements:
3.2.1 Forming (see 4.1.2),
3.2.2 Rolled or cut threads (see 4.1.3),
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from Global Engineering Documents, 15 Inverness Way, East Englewood, CO 80112-5704, http://www.global.ihs.com.
Available from Japanese Industrial Standards Committee (JIS) 1-3-1 Kasumigaski, Chiyoda-ku, Tokyo 100-8901, Japan. http:www.jisc.go.jp
F593 − 22
3.2.3 Composition (see 6.2),
3.2.4 Corrosion Resistance (see 8.1),
3.2.5 Finish (see 10.3),
3.2.6 Rejection (see 16.1), and
3.2.7 Test report (see 17.2).
3.2.8 Supplementary requirements, if any, to be specified on the order (see S1 through S8), and
3.2.9 ASTM specification and year of issue. When year of issue is not specified, fasteners shall be furnished to the latest issue.
NOTE 1—Example 10 000 pieces, Hex Cap Screw, 0.250 in. −20 × 3.00 in., Alloy Group 1, Condition CW, Furnish Test Report, Supplementary
Requirement S3.
4. Manufacture
4.1 Manufacture:
4.1.1 Specifications A276, A493, A564/A564M, and A582/A582M are noted for information only as suitable sources of material
for the manufacture of bolts, hex cap screws, and studs to this specification.
4.1.2 Forming—Unless otherwise specified, the fasteners shall be cold formed, hot formed, or machined from suitable material
at the option of the manufacturer.
4.1.3 Threads—Unless otherwise specified, the threads shall be rolled or cut at the option of the manufacturer.
4.2 Condition—The fasteners shall be furnished in the following conditions, unless specified to be furnished in one of the optional
conditions:
Condition Furnished Unless Optional Conditions (must
Alloy Group Otherwise Specified be specified)
1, 2, 3 CW AF, A, SH
4 CW A
5 H HT
6 H HT
7 AH none
A— Machined from annealed or solution-annealed stock thus retaining the
properties of the original material; or hot-formed and solution annealed.
AF— Headed and rolled from annealed stock and then reannealed.
AH— Solution-annealed and age-hardened after forming.
CW— Headed and rolled from annealed stock thus acquiring a degree of cold
work. Sizes 0.75 in. and larger may be hot-worked and solution-
annealed.
H— Hardened and tempered at 1050°F (565°C) minimum.
H— Hardened and tempered at 1050 °F (565 °C) minimum.
HT— Hardened and tempered at 525°F (274°C) minimum.
HT— Hardened and tempered at 525 °F (274 °C) minimum.
SH— Machined from strain-hardened stock or cold-worked to develop the
specific properties.
5. Heat Treatment
5.1 Alloy Groups 1, 2, and 3 (Austenitic Alloys 303, 303Se, 304, 304 L, 305, 316, 316 L, 321, 347, 384, XM1, 18-9LW, 302HQ,
and 304J3):
5.1.1 Condition A—When Condition A is specified, the austenitic alloys shall be heated to 19001900 °F 6 50°F (103850 °F
F593 − 22
(1038 °C 6 28°C),28 °C), at which time the chromium carbide will go into the solution, be held for a sufficient time, and then be
cooled at a rate sufficient to prevent precipitation of the carbide and to provide the specified properties.
5.1.2 Condition CW—When Condition CW is specified, the austenitic alloys shall be annealed in accordance with 5.1.1, generally
by the raw material manufacturer and then cold worked to develop the specified properties.
5.1.3 Condition AF—When Condition AF is specified, the austenitic alloys shall be annealed in accordance with 5.1.1 after all cold
working (including heading and threading) has been completed.
5.2 Alloy Group 4 (Ferritic Alloys 430 and 430F):
5.2.1 Condition A—The ferritic alloys shall be heated to a temperature of 14501450 °F 6 50°F (78850 °F (788 °C 6
28°C),28 °C), held for an appropriate time, and then air cooled to provide the specified properties.
5.2.2 Condition CW—When Condition CW is specified, the ferritic alloys shall be annealed in accordance with 5.2.1, generally
by the raw material manufacturer and then cold worked to develop the specified properties.
5.2.3 Condition AF—When Condition AF is specified, the ferritic alloys shall be annealed in accordance with 5.2.1 after all cold
working (including heading and threading) has been completed.
5.3 Alloy Group 5 (Martensitic Alloys 410, 416, and 416Se):
5.3.1 Condition H—When Condition H is specified, the Martensitic Alloys 410, 416, and 416Se shall be hardened and tempered
by heating to 18501850 °F 6 50°F (101050 °F (1010 °C 6 28°C)28 °C) sufficient for austenitization, held for at least ⁄2 h and
rapid air- or oil-quenched, and then reheating to 1050°F (565°C)1050 °F (565 °C) minimum for at least 1 h and air cooled to
provide the specified properties.
5.3.2 Condition HT—When Condition HT is specified, the Martensitic Alloys 410, 416, and 416Se shall be hardened and tempered
by heating to 18501850 °F 6 50°F (101050 °F (1010 °C 6 28°C)28 °C) sufficient for austenitization, held for at least ⁄2 h and
rapid air- or oil-quenched, and then reheating to 525°F (274°C)525 °F (274 °C) minimum for at least 1 h and air cooled to provide
the specified properties.
5.4 Alloy Group 6 (Martensitic Alloy 431):
5.4.1 Conditions H and HT—Martensitic Alloy 431 shall be hardened and tempered in accordance with 5.3.1 and 5.3.2 as
applicable.
5.5 Alloy Group 7 (Precipitation Hardening Alloy 630):
5.5.1 Condition AH—Precipitation Hardening Alloy 630 shall be solution annealed and aged by heating to 19001900 °F 6 25°F
(103825 °F (1038 °C 6 14°C)14 °C) for at least ⁄2 h and rapid air- or oil-quenched to 80°F (27°C)80 °F (27 °C) maximum, then
reheating to a temperature of 11501150 °F 6 15°F (62115 °F (621 °C 6 8°C)8 °C) for 4 h and air cooled to provide the specified
properties.
6. Chemical Composition
6.1 Alloy Groups—It is the intent of this specification that fasteners shall be ordered by alloy group numbers, which include alloys
considered to be chemically equivalent for general purpose use. The alloy groupings are shown as follows. The purchaser has the
option of ordering a specific alloy, in stead of an alloy group number, as permitted in 6.2.2.
Alloy Group Alloys
1 304, 304 L, 305, 384, 18-9LW, 302HQ,
A
304J3
2 316, 316 L
3 321, 347
B
4 430
C
5 410
6 431
7 630
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A
When approved by the purchaser, Alloys 303, 303Se, or XM1 may be furnished.
B
When approved by the purchaser, Alloy 430F may be furnished.
C
When approved by the purchaser, Alloys 416 or 416Se may be furnished.
6.2 Chemical Composition Limits:
6.2.1 Ordering by Alloy Group—Unless otherwise specified on the inquiry and order (see Supplementary Requirement S4), the
choice of an alloy from within a group shall be at the discretion of the fastener manufacturer as required by his method of fastener
fabrication and material availability. The specific alloy used by the fastener manufacturer shall be clearly identified on any
certification required by the order and shall have a chemical composition conforming to the requirements of Table 1 for the specific
alloy.
6.2.2 Ordering by Specific Alloy—When ordered by a specific alloy number, the fasteners shall conform to the chemical
composition limits of Table 1 for the specific alloy.
6.3 Product Analysis:
6.3.1 When performed, product analysis to determine chemical composition shall be performed on at least one fully manufactured
finished fastener representing each lot. The chemical composition thus determined shall conform to the requirements of Table 1
for the specified alloy or alloy group as appropriate, subject to the Product Analysis Tolerance in Specifications A484/A484M and
A555/A555M.
TABLE 1 Chemical Requirements
Alloy UNS Alloy Composition, % maximum except as shownshown, ellipses indicate no requirement for listed element
Group Designa-
Carbon Manga- Phos- Sulfur Silicon Chromium Nickel Copper Molybdenum Others
tion
nese phorus
Austenitic Alloys
A
1 S30300 303 0.15 2.00 0.20 0.15 min 1.00 17.0 to 19.0 8.0 to 10.0 . . . 0.60 max . . .
A
1 S30300 303 0.15 2.00 0.20 0.15 min 1.00 17.0 to 19.0 8.0 to 10.0 . . . 0.60 . . .
1 S30323 303 Se 0.15 2.00 0.20 0.060 1.00 17.0 to 19.0 8.0 to 10.0 . . . . . . Se 0.15 min
1 S30400 304 0.08 2.00 0.045 0.030 1.00 18.0 to 20.0 8.0 to 10.5 1.00 . . . . . .
B
1 S30400 304 0.08 2.00 0.045 0.030 1.00 18.0 to 20.0 8.0 to 10.5 . . . . . .
1 S30403 304 L 0.03 2.00 0.045 0.030 1.00 18.0 to 20.0 8.0 to 12.0 1.00 . . . . . .
B
1 S30403 304 L 0.03 2.00 0.045 0.030 1.00 18.0 to 20.0 8.0 to 12.0 . . . . . .
1 S30500 305 0.12 2.00 0.045 0.030 1.00 17.0 to 19.0 10.5 to 13.0 1.00 . . . . . .
B
1 S30500 305 0.12 2.00 0.045 0.030 1.00 17.0 to 19.0 10.0 to 13.0 . . . . . .
A
1 S38400 384 0.08 2.00 0.045 0.030 1.00 15.0 to 17.0 17.0 to 19.0 . . . 0.50 max . . .
1 S38400 384 0.08 2.00 0.045 0.030 1.00 15.0 to 17.0 17.0 to 19.0 . . . . . . . . .
1 S20300 XM1 0.08 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 . . . . . .
1 S20300 XM1 0.08 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 . . .
1 S30430 18–9LW 0.10 2.00 0.045 0.030 1.00 17.0 to 19.0 8.0 to 10.0 3.0 to 4.0 . . . . . .
1 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 . . . . . .
B
1 . . . 304J3 0.08 2.00 0.045 0.030 1.00 17.0 to 19.0 8.0 to 10.5 1.00 to 3.00 . . . . . .
C
1 . . . 304J3 0.08 2.00 0.045 0.030 1.00 17.0 to 19.0 8.0 to 10.5 1.00 to 3.00 . . . . . .
2 S31600 316 0.08 2.00 0.045 0.030 1.00 16.0 to 18.0 10.0 to 14.0 . . . 2.00 to 3.00 . . .
2 S31603 316 L 0.03 2.00 0.045 0.030 1.00 16.0 to 18.0 10.0 to 14.0 . . . 2.00 to 3.00 . . .
3 S32100 321 0.08 2.00 0.045 0.030 1.00 17.0 to 19.0 9.0 to 12.0 . . . . . . Ti 5× C min
Cb+Ta 10 × C
3 S34700 347 0.08 2.00 0.045 0.030 1.00 17.0 to 19.0 9.0 to 13.0 . . . . . .
min
D
3 S34700 347 0.08 2.00 0.045 0.030 1.00 17.0 to 19.0 9.0 to 13.0 . . . . . . Nb 10 × C min
Ferritic Alloys
4 S43000 430 0.12 1.00 0.040 0.030 1.00 16.0 to 18.0
. . . . . . . . .
A
4 S43020 430F 0.12 1.25 0.060 0.15 min 1.00 16.0 to 18.0 0.60 max
Martensitic Alloys
5 S41000 410 0.15 1.00 0.040 0.030 1.00 11.5 to 13.5
5 S41600 416 0.15 1.25 0.060 0.15 min 1.00 12.0 to 14.0 . . . . . .
A
0.60 max
5 S41623 416Se 0.15 1.25 0.060 0.060 1.00 12.0 to 14.0 Se 0.15 min
6 S43100 431 0.20 1.00 0.040 0.030 1.00 15.0 to 17.0 1.25 to 2.50 . . . . . . . . .
Precipitation Hardening Alloy
Cb+Ta
7 S17400 630 0.07 1.00 0.040 0.030 1.00 15.0 to 17.5 3.0 to 5.0 3.0 to 5.0 . . .
0.15–0.45
D
7 S17400 630 0.07 1.00 0.040 0.030 1.00 15.0 to 17.5 3.0 to 5.0 3.0 to 5.0 . . . Nb 0.15–0.45
A
At manufacturer’s option, determined only when intentionally added.
B
1.00 % Cu max allowed by this standard for formability at manufacturer’s option.
C
304J3 from JIS Standard G4309.
D
Niobium formerly known as Colombium (Cb)
F593 − 22
6.3.2 In the event of discrepancy, a referee chemical analysis of samples from each lot shall be made in accordance with 14.1.
7. Mechanical Properties
7.1 The finished fasteners shall meet the applicable mechanical property and test requirements of Table 2 and Table 3 as
appropriate for the specified alloy group and condition and shall be tested for conformance to the mechanical property requirements
as specified herein.
7.2 Fasteners having a nominal thread diameter-length combination as follows:
Thread Diameter, in. Thread Length, in.
0.75 or less 2.25 D or longer
Over 0.75 3 D or longer
and a breaking load of 120 000 lbf (535 kN) or less shall be tested full size and shall meet the full-size tensile (minimum and
maximum) and yield strength requirements in Table 2 for the specified alloy.
7.3 Fasteners having a nominal thread diameter-length combination in accordance with 7.2 and a breaking load exceeding 120 000
lbf (535 kN) shall be tested full-size and shall meet the full size tensile (minimum and maximum) and yield strength properties
in Table 2. When equipment of sufficient capacity for such tests is not available, or if excessive length of the fasteners makes
full-size testing impractical, use of standard or round specimens that meet the “machined specimen test tensile properties” in Table
2 is permitted. In the event of discrepancy or dispute between test results obtained from full-size finished fasteners and standard
or round specimens, the referee method shall be tests performed on full-size finished fasteners.
7.4 Fasteners that are too short (lengths less than that specified in 7.2 (see Test Methods F606/F606M and Table 4); have
insufficient threads for tension; or have drilled or undersized heads, drilled or reduced bodies, and so forth, that are weaker than
the thread section, shall not be subject to tension tests but shall conform to the hardness (minimum and maximum) requirements
of Table 2.
8. Corrosion Resistance
8.1 Carbide Precipitation:
8.1.1 Rod, bar, and wire in the austenitic Alloy Groups 1, 2, and 3, except the free-machining grades, 303 and 303Se, used to make
fasteners in accordance with this specification shall be capable of passing the test for susceptibility to intergranular corrosion as
specified in Practice E of Practices A262.
8.1.2 As stated in Practice A262, samples may be subjected to the faster and more severe screening test in accordance with
Practice A. Failing Practice A, specimens shall be tested in accordance with Practice E and be considered satisfactory if passing
Practice E.
9. Dimensions
9.1 Bolts and Hex Cap Screws:
9.1.1 Unless otherwise specified, the d
...