ASTM F594 Stainless Steel Nuts

ASTM F594 - Standard Specification for Stainless Steel Nuts

This specification covers the requirements for Stainless Steel Hex Nuts in imperial size 1/4 inch to 1 1/2 inch, inclusive for number of alloys in common use and intended for service applications requiring general corrosion resistance. ASTM F594 covers seven groups of stainless steel alloys, including twelve austenitic, two ferritic, four martensitic and one precipitation hardening. BoltPort manufactures Hex Nuts in most alloys under ASTM F594 specification, duly tested and supply with EN 10204 Type 3.1 Certification. ASTM F594A, F594C, F594D, F594F, F594G, F594H are most commonly produced nuts.

ASTM F594 Alloy Categories

Group AlloyA ConditionB
1 304, 305, 384, 304L, 18-9LW, 302HQD (CW) Cold WorkedD
2 316, 316L (CW) Cold WorkedD
3 321, 347 (CW) Cold WorkedD
4 430E (CW) Cold WorkedD
5 410F (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
B See section 4.2 of F593 for options
C When approved by the purchaser, alloys 303, 303Se, or XM1 may be furnished.
D Sizes 0.75 inch and larger may be hot worked and solutoon annealed.
E When approved by the purchaser, alloy 430F may be furnished.
F When approved by the purchaser, alloys 416 or 416Se may be furnished.

ASTM F593 Bolts Supply Conditions

Alloy Group Condition Furnished Unless Otherwise Specified Optional Conditions (must 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 0.75inch and larger may be hot worked and solution annealed.
H - Hardened and tempered at 1050°F (565°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.

List of Heat Treatments

Heat Treatments for Austenitic Alloys

Condition A - When Condition A is specified, the austenitic alloys shall be heated to 1900+/- 50°F ( 1038 +/- 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.

Condition CW - When Condition CW is specified, the austenitic alloys shall be annealed in accordance with Condition A, generally by the raw material manufacturer and thenc old worked to develop the specified properties.

Condition AF - When Condition AF is specified, the austenitic alloys shall be annealed in accordance to Condition A after all cold working (including heading and threading) has been completed.

Heat Treatments for Ferritic Alloys

Condition A - The ferritic alloys shall be heated to a temperature of 145 +/- 50°F (788 +/- 28°C), held for an appropriate time, and then air cooled to procide the specified properties.

Condition CW - When Condition CW is specified, the ferritic alloys shall be annealed in accordance to above condition A for ferritic alloys, generally by the raw material manufacturer and then cold worked to develop the specified properties.

Condition AF - When Condition AF is specified, the ferritic alloys shall be annealed in accordance to same above condition A (Ferritic Alloys) after all cold working (including heading and threading) has been completed.

Heat Treatments for Martensitic Alloys (SS Alloy 410, 416 & 416Se)

Condition H - When Condition H is specified, the martensitic alloys 410, 416 and 416Se shall be hardened and tempered by heating to 1850 +/- 50°F (1010 +/- 28°C) sufficient for austenitization, held for atleast 1/2 hour and rapid air or oil quenched, and then reheating to 1050°F (565°C) minimum for atleast 1 hour and air cooled to develop the specified properties.

Condition HT - When Condition HT is specified, the martensitic alloys 410, 416 and 416Se shall be hardened and tempered by heating to 1850 +/- 50°F (1010 +/- 28°C) sufficient for austenitization, held for atleast 1/2 hour and rapid air or oil quenched, and then reheating to 525°F (272°C) minimum for atleast 1 hour and air cooled to develop the specified properties.

Heat Treatments for Martensitic Alloys ( SS Alloy 431)

Condition H and HT - Martensitic Alloy 431 shall be hardened and tempered in accordance with above condition H or HT (Martensitic 410, 416 and 416Se) as applicable.

Heat Treatments for Precipitation Hardening Alloy 630

Conditon AH - Precipitation Hardening Alloy 630 shall be solution annealed and aged by heating to 1900 +/- 25°F (1038 +/- 14°C) for atleast 1/2 hour and rapid air or oil quenched to 80°F (27*C) maximum, then reheating to a temperature of 1150 +/- 15°F (621 +/- 8°C) for 4 hour and air cooled to develop the specified properties.

ASTM F593 Chemical Requirements

Composition, %, maximum except as shown
UNS Designation Alloy Group Alloy Carbon Manganese Phosphorus Sulfur Silicon Chromium Nickel Copper Molybdenum Others
Austenitic Alloys
S30200 1 303 0.15 2.00 0.200 0.150 min 1 17.0 - 19.0 8.0 - 10.0 -- 0.60 maxA --
S30323 1 303 Se 0.15 2.00 0.200 0.060 1 17.0 - 19.0 8.0 - 10.0 -- -- Se 0.15 min
A30400 1 304 0.08 2.00 0.045 0.030 1 18.0 - 20.0 8.0 - 10.5 1.00 -- --
S30403 1 304 L 0.03 2.00 0.045 0.030 1 18.0 - 20.0 8.0 - 12.0 1.00 -- --
S30500 1 305 0.12 2.00 0.045 0.030 1 17.0 - 19.0 10.5 - 13.0 1.00 -- --
S38400 1 384 0.08 2.00 0.045 0.030 1 15.0 - 17.0 17.0 - 19.0 -- 0.50 maxA --
S20300 1 XM1 0.08 5.00 - 6.50 0.040 0.18 - 0.35 1 16.0 - 18.0 5.0 - 6.5 1.75 - 2.25 -- --
S30430 1 18-9LW 0.10 2.00 0.045 0.030 1 17.0 - 19.0 8.0 - 10.0 3.0 - 4.0 -- --
S30433 1 302HQ 0.03 2.00 0.045 0.030 1 17.0 - 19.0 8.0 - 10.0 3.0 - 4.0 -- --
S31600 2 316 0.08 2.00 0.045 0.030 1 16.0 - 18.0 10.0 - 14.0 -- 2.0 - 3.0 --
S31603 2 316 L 0.03 2.00 0.045 0.030 1 16.0 - 18.0 10.0 - 14.0 -- 2.0 - 3.0 --
S32100 3 321 0.08 2.00 0.045 0.030 1 17.0 - 19.0 9.0 - 12.0 -- -- Ti 5 x C min
S34700 3 347 0.08 2.00 0.045 0.030 1 17.0 - 19.0 9.0 - 13.0 -- -- Cb+Ta 10 x C min
Ferritic Alloys
S43000 4 430 0.12 1.00 0.040 0.030 1 16.0 - 18.0 -- -- -- --
S43020 4 430F 0.12 1.25 0.060 0.150 min 1 16.0 - 18.0 -- -- 0.60 maxA --
Martensitic Alloys
S41000 5 410 0.15 1.00 0.040 0.030 1 11.5 - 13.5 -- -- -- --
S41600 5 416 0.15 1.25 0.060 0.150 min 1 12.0 - 14.0 -- -- 0.60 maxA --
S41623 5 416 Se 0.15 1.25 0.060 0.060 1 12.0 - 14.0 -- -- Se 0.15 min --
S43100 6 431 0.20 1.00 0.040 0.030 1 15.0 - 17.0 1.25 - 2.50 -- -- --
Precipitation Hardening Alloy
S17400 7 630 0.07 1.00 0.040 0.030 1 15.0 - 17.5 3.0-5.0 -- -- Cb+Ta 0.15 - 0.45

A At manufacturer's options, determined only when intentionally added.

ASTM F593 Mechanical Properties

Stainless Steel Alloys ConditionB Alloy Mechanical Property Marking Nominal Diameter, inch Proof Load, ksi, min Rockwell Hardness
Austenitic Alloys
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) AF F593A 1/4 to 1-1/2, incl. 70 B85 max, incl.
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) A F593B 1/4 to 1-1/2, incl. 75 B65 to 95, incl.
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) CW1 F593C 1/4 to 5/8, incl. 100 B95 to C322, incl.
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) CW2 F593D 3/4 to 1-1/2, incl. 85 B80 to C32, incl.
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) SH1 F593A 1/4 to 5/8, incl. 120 C24 to C36, incl.
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) SH2 F593B 3/4 to 1, incl. 110 C20 to C32, incl.
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) SH3 F593C 1-1/8 to 1-1/4, incl. 100 B95 to C30, incl.
1 (303, 304, 304L, 305, 384, XM1, 18-9LW, 302HQ, 303Se) SH4 F593D 1-3/8 to 1-1/2, incl. 85 B90 to C28, incl.
2 (316, 316L) AF F593E 1/4 to 1-1/2", incl. 70 B85 max, incl.
2 (316, 316L) A F593F 1/4 to 1-1/2", incl. 75 B65 to 95, incl.
2 (316, 316L) CW1 F593G 1/4 to 5/8, incl. 100 B95 to C322, incl.
2 (316, 316L) CW2 F593H 3/4 to 1-1/2, incl. 85 B80 to C32, incl.
2 (316, 316L) SH1 F593E 1/4 to 5/8, incl. 120 C24 to C36, incl.
2 (316, 316L) SH2 F593F 3/4 to 1, incl. 110 C20 to C32, incl.
2 (316, 316L) SH3 F593G 1-1/8 to 1-1/4, incl. 100 B95 to C30, incl.
2 (316, 316L) SH4 F593H 1-3/8 to 1-1/2, incl. 85 B90 to C28, incl.
3 (321, 347) AF F593J 1/4 to 1-1/2, incl. 70 B85 max
3 (321, 347) A F593K 1/4 to 1-1/2, incl. 75 B65 to 95, incl.
3 (321, 347) CW1 F593L 1/4 to 5/8, incl. 100 B95 to C322, incl.
3 (321, 347) CW2 F593M 3/4 to 1-1/2, incl. 85 B80 to C32, incl.
3 (321, 347) SH1 F593J 1/4 to 5/8, incl. 120 C24 to C36, incl.
3 (321, 347) SH2 F593K 3/4 to 1, incl. 110 C20 to C32, incl.
3 (321, 347) SH3 F593L 1-1/8 to 1-1/4, incl. 100 B95 to C30, incl.
3 (321, 347) SH4 F593M 1-3/8 to 1-1/2, incl. 85 B90 to C28, incl.
Ferritic Alloys
4 (430, 430F) A F593N 1/4 to 1-1/2, incl. 55 B85 max
4 (430, 430F) CW1 F593V 1/4 to 5/8, incl. 60 B75 to 98, incl.
4 (430, 430F) CW2 F593W 3/4 to 1-1/2, incl. 55 B65 to 95, incl.
Martensitic Alloys
5 (410, 416, 416Se) H F593P 1/4 to 1-1/2, incl. 100 C20 to 30, incl.
5 (410, 416, 416Se) HT F593R 1/4 to 1-1/2, incl. 160 C34 to 45, incl.
6 (431) H F593S 1/4 to 1-1/2, incl. 125 C25 to 32, incl.
6 (431) HT F593T 1/4 to 1-1/2, incl. 180 C40 to 48, incl.
Precipitation Hardening Alloy
7 (630) AH F593U 1/4 to 1-1/2, incl. 135 C28 to 38, incl.

A Minimum values except where shown as maximum or as a range.
B legend of conditions:
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 0.75inch and larger may be hot worked and solution annealed.
H - Hardened and tempered at 1050°F (565°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.
C The yield and tensile strength values for full size products shall be computed by dividing the yield and maximum tensile load value by the stress area for the product size and thread sizes determined in accordance with Test Methods F606.
D Yield strength is the stress at which an offset of 0.2 & gauge length occurs.

Mechanical Test Requirements for Nuts

Product Proof Stress, ksi Test Conducted Using Full Size Product
Hardness Proof Load
Jam, slotted and castle nuts All A B
All other nuts Upto 120 000 A A
All other nuts Over 120 000 Option AA Option B

ASTM F594 Tensile Stress Areas and Threads per Inch

Nominal Size, inch. Coarse Threads - UNC Fine Threads - UNF Thread Series - 8UN
Threads / inch Stress AreaA, in2 Threads / inch Stress AreaA, in2 Threads / inch Stress AreaA, in2
1/4 (0.250) 20 0.0318 28 0.0364 -- --
5/16 (0.3125) 18 0.0524 24 0.0580 -- --
3/18 (0.375) 16 0.0775 24 0.0878 -- --
7/16 (0.4375) 14 0.1063 20 0.1187
1/2 (0.500) 13 0.1419 20 0.1599
9/16 (0.5625) 12 0.1820 18 0.2030
5/8 (0.625) 11 0.2260 18 0.2560
3/4 (0.750) 10 0.3340 16 0.3730
7/8 (0/875) 9 0.4620 14 0.5090
1 8 0.6060 12 0.6630
1 1/8 (1.125) 7 0.7630 12 0.8560 8 0.790
1 1/4 (1.250) 7 0.9690 12 1.0730 8 1.000
1 3/8 (1.375) 6 1.1550 12 1.3150 8 1.233
1 1/2 (1.500) 6 1.4050 12 1.5810 8 1.492

A Tensile stress areas are computed using the following formula: AB = 0.7854 [D- (0.9743/n)]2
Where:
AB = Tensile stress area, inch2,
D = Nominal size (basic major diameter), in., and,
n = number of threads per inch.