The chemical and mechanical properties of stainless steel nuts for use with ASTM F593 fasteners with diameters ranging from 1/4 to 1-1/2 inches, inclusive, are specified in ASTM F594. These nuts are available in seven different alloy groups and are intended for a wide range of applications. The most common grades in the ASTM F594 standard are listed below. A few additional ASTM F594 grades aren't listed here because they're less prevalent. The chemical table is limited to the most common alloy grades used for each alloy group, while the mechanical table is limited to the most common alloy groups 1 and 2.
| Alloy Group | UNS Designation | Alloy | C | Mn | P | S | Si | Cr | Ni | Cu | Mo | Others |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| S34700 | 347 | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 17.0 to 19.0 | 9.0 to 13.0 | . . . | . . . | - | Cb+Ta 10 × C min |
| Stainless Alloy Group | ConditionB | Alloy Mechanical Property Marking | Nominal Diam- eter, in. | Proof Stress, Hex Nuts ksi, min | Proof Stress, Heavy Hex Nuts ksi, minC | Rockwell Hardness |
|---|---|---|---|---|---|---|
| ASTM F594 Alloy Group 3 (347) |
AF | F594J | 1/4 to 11/2 , incl | 70 | 76 | B85 max |
| A | F594K | 1/4 to 11/2 , incl | 75 | 81 | B65 to 95, incl | |
| CW1 | F594L | 1/4 to 5/8 , incl | 100 | 108 | B95 to C35, incl | |
| CW2 | F594M | 3/4 to 11/2 , incl | 85 | 92 | B80 to C35, incl | |
| SH1 | F594J | 1/4 to 5/8 , incl | 120 | 130 | C24 to C36, incl | |
| SH2 | F594K | 3/4 to 1, incl | 110 | 119 | C20 to C32, incl | |
| SH3 | F594L | 11/8 to 11/4 , incl | 100 | 108 | B95 to C30, incl | |
| SH4 | F594M | 13/8 to 11/2 , incl | 85 | 92 | B90 to C28, incl |