The ASTM F2281 standard covers the chemical and mechanical requirements for stainless steel and nickel alloy bolts, hex cap screws, and studs with a diameter of 1/4 inch and larger that are intended for use at temperatures up to 1800°F (982°C) and in applications where heat resistance and the effects of high temperature are important. This specification covers a wide range of materials that can be used at high temperatures due to unique alloy qualities, as well as environmental requirements such as corrosive conditions. Specifications A276, A484/A484M, A493, A564/A564M, A582/A582M, and B637 are listed here solely as possible sources of material for making bolts, hex cap screws, and studs to this specification.
| Alloy | C | Mn | P | S | Si | Cr | Ni | Cu | Mo | Other |
|---|---|---|---|---|---|---|---|---|---|---|
| ASTM F2281 718 Type III, Class C | 0.08 | 0.35 | 0.015 | 0.015 | 0.35 | 17.0-21.0 | 50.0-55.0 | 0.30 | 2.80-3.30 | Ti 0.65-1.15 Co 1.00 max Al 0.20-0.80 B 0.006 max Cb + Ta 4.75-5.50 Fe remainder |
| Alloy Grades | Condition | Marking | Nominal Diameter, in. | Full-Size Tests | Rockwell Hardness | Machined Specimen Tests | |||
|---|---|---|---|---|---|---|---|---|---|
| Tensile Strength, min, ksi | Yield Strength, min, ksi | Tensile Strength, min, ksi | Yield Strength, min, ksi | Elongation 4D, min % | |||||
| ASTM F2281 718 Type III, Class C | AH4 | F3G | All diameters | 185 | 150 | 36 to 48 HRC | 180 | 150 | 12 |