ASTM B670
Alloy 718 chemistry and precipitation-hardened test requirements, including thickness-dependent tensile and stress-rupture results.
Precipitation-Hardening Nickel Alloy Plate, Sheet & Strip
Edition: B670-07
1 linked material grade
Material requirements.
Clearly organized.
Alloy 718 chemistry and precipitation-hardened test requirements, including thickness-dependent tensile and stress-rupture results.
Material forms, conditions and dimensional ranges are shown alongside the relevant property values.
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Composition & Mechanical Properties
| Grade / UNS | C % | Mn % | Si % | P % | S % | Cr % | Co % | Mo % | Nb + Ta % | Ti % | Al % | Fe | Cu % | Ni % | B % |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Alloy 718 N07718 | ≤0.080 | ≤0.35 | ≤0.35 | ≤0.015 | ≤0.015 | 17.0–21.0 | ≤1.0 if determined | 2.80–3.30 | 4.75–5.50 | 0.65–1.15 | 0.20–0.80 | Remainder | ≤0.30 | 50.0–55.0 | ≤0.006 |
Composition values are mass percentages. ≤ indicates a maximum; ≥ indicates a minimum.
| Grade / UNS | Product form / condition | Tensile min (MPa) | Yield min (MPa) | Elongation min (%) | Hardness |
|---|---|---|---|---|---|
| Alloy 718 N07718 | After precipitation heat treatment · ≤1.0 in. (25.4 mm) | 1241 | 1034 | 12 | — |
| Alloy 718 N07718 | After precipitation heat treatment · >1.0–2.25 in. (25.4–57.2 mm) | 1241 | 1034 | 10 | — |
Stress-Rupture Properties · 1200°F (649°C)
| Grade / UNS | Nominal thickness | Stress (MPa) | Life min (h) | Elongation min (%) |
|---|---|---|---|---|
| Alloy 718 N07718 | ≤0.015 in. (0.38 mm) | 655 | 23 | — |
| Alloy 718 N07718 | >0.015–0.025 in. (0.38–0.64 mm) | 655 | 23 | 4 |
| Alloy 718 N07718 | >0.025–1.5 in. (0.64–38.1 mm) | 690 | 23 | 4 |
- Material is supplied annealed; the manufacturer demonstrates the listed tensile and rupture properties after precipitation heat treatment.
- The specified treatment heats to 1325 ±25°F for 8 h, furnace-cools to 1150 ±25°F, and continues until total precipitation-treatment time reaches 18 h, followed by air cooling.
- Stress-rupture testing is at 1200°F (649°C); the table below retains the thickness ranges and stress levels.
- Iron is determined by difference. The cobalt limit applies if determined.
From material form
to gasket component.
Review the listed material grade and its delivery condition when selecting winding strip or ring stock for a specified gasket design.
Material standards and gasket standards serve different purposes.
ASTM B670 addresses the material forms identified on this page. Finished metallic gasket requirements are addressed separately by the applicable gasket standard.
Explore ASME B16.20 →Common questions
Material coverage and property conditions for this standard.
Which website material grades are included?
Alloy 718.
What edition is used for these tables?
The tables use ASTM B670-07.
Are material properties independent of condition?
No. The mechanical table identifies the applicable product form, condition and dimensional range for each listed row.