Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
ASTM B637 — A286 Precipitation-Hardenable Bar
ASTM B637 is the ASTM industrial specification for A286 (UNS S66286) precipitation-hardenable bar — covers the alloy in solution-treated and / or aged condition for non-aerospace industrial high-temperature service. The spec is the industrial alternative to AMS 5731 / AMS 5732 for petrochemical, oil & gas, gas-turbine accessory, and chemical-process applications where AS9100D aerospace AQMS is not required. ASTM B637 is also referenced for some ASME pressure-vessel applications where ASTM A638 grade 660 is excessive. See parent A286 AMS / ASTM specifications hub, related A286 round bar, sister specs AMS 5731, AMS 5732.
Spec Scope & Coverage
ASTM B637 covers A286 precipitation-hardenable bar in solution-treated and / or aged conditions. Material is VIM-melted (single melt acceptable) ingot, hot-rolled to bar diameter, optionally cold-drawn for tighter tolerance, then heat-treated per condition specified. Sol-treated condition: hardness 24-28 HRC. Sol-treated and aged condition: hardness 29-32 HRC; tensile ≥ 895 MPa; yield ≥ 655 MPa. Used as industrial bar substitute for non-aerospace applications.
A286 Chemical Composition (UNS S66286)
| Element | Min % | Max % | Notes |
|---|---|---|---|
| Iron (Fe) | Balance | Balance | ~53 % typical |
| Nickel (Ni) | 24.0 | 27.0 | Solid-solution stabilizer |
| Chromium (Cr) | 13.5 | 16.0 | Corrosion + oxidation resistance |
| Titanium (Ti) | 1.90 | 2.35 | Gamma-prime former (Ni3Ti) |
| Molybdenum (Mo) | 1.00 | 1.50 | Solid-solution strengthener |
| Vanadium (V) | 0.10 | 0.50 | Carbide stabilizer |
| Aluminium (Al) | 0 | 0.35 | Gamma-prime former (Ni3Al) |
| Boron (B) | 0.001 | 0.010 | Grain-boundary strengthening |
| Carbon (C) | 0 | 0.08 | Per ASTM A453 |
| Manganese (Mn) | 0 | 2.00 | Per ASTM A453 |
| Silicon (Si) | 0 | 1.00 | Per ASTM A453 |
| Phosphorus (P) | 0 | 0.025 | Trace impurity |
| Sulphur (S) | 0 | 0.015 | Trace impurity |
ASTM B637 — A286 Precipitation-Hardenable Bar — Spec Requirements
| Property | ASTM B637 requirement | Notes |
|---|---|---|
| Form | Bar (round, hex, square) | Industrial scope |
| Heat treatment | Sol-treated or sol+aged | Per condition specified |
| Tensile (sol+aged) | ≥ 895 MPa (130 ksi) | Same as AMS 5732 |
| Yield (sol+aged) | ≥ 655 MPa (95 ksi) | Same as AMS 5732 |
| Hardness (sol+aged) | 29-32 HRC | Industrial standard |
| Surface finish | Hot-rolled pickled or cold-drawn | Per drawing |
| Inspection | EN 10204 type 3.1 mill cert | Industrial standard |
| AQMS | ISO 9001:2015 | Industrial; aerospace lots add AS9100D |
When to Specify ASTM B637 — A286 Precipitation-Hardenable Bar
- Industrial high-temperature bar: ASTM B637 sol+aged for industrial gas-turbine accessory, refinery, chemical-process applications.
- Cost-efficient AMS substitute: When aerospace AS9100D AQMS not required, ASTM B637 is ~10-15 % cheaper than AMS 5732.
- ASME pressure-vessel applications: ASTM B637 referenced for some ASME B31.3 industrial pressure-piping applications.
- NACE MR0175 sour-service: ASTM B637 with hardness ≤ HRC 35 verification — sour-service compliant.
- Aerospace bar alternative: AMS 5732 for aerospace; AMS 5731 for sol-treated bar with downstream aging.
- Forgings alternative: ASTM A638 grade 660 for forgings instead of bar.
ASTM B637 — A286 Precipitation-Hardenable Bar — Frequently Asked Questions
What is ASTM B637?
ASTM industrial spec for A286 (UNS S66286) precipitation-hardenable bar. The industrial alternative to AMS 5731 / 5732 for non-aerospace high-temperature service. Used in petrochemical, oil & gas, gas-turbine accessory, and chemical-process applications.
ASTM B637 vs AMS 5732 — what's the difference?
Same chemistry (UNS S66286), same heat-treatment, similar mechanical properties. Difference is scope and AQMS: ASTM B637 is industrial under ISO 9001; AMS 5732 is aerospace under AS9100D with AS9102 first-article inspection. For aerospace cite AMS 5732; for industrial cite ASTM B637 (~10-15 % cost savings).
Is ASTM B637 ASME-acceptable for pressure vessels?
Yes for some applications. ASTM B637 is referenced in ASME B31.3 industrial pressure-piping. For ASME Section III nuclear pressure-vessel applications, ASTM A638 grade 660 is the canonical spec; ASTM B637 may be alternate-acceptable in some cases.
Can ASTM B637 be NACE MR0175 sour-service compliant?
Yes — when supplied with hardness ≤ HRC 35 (HV ≤ 327) per NACE MR0175 / ISO 15156-3 for sour-service oilfield applications. Specify on PO; each heat receives Vickers traverse before release.
What's the lead time on ASTM B637 bar?
Standard sizes 5-50 mm: 4-6 weeks from heat release. Larger sizes 50-200 mm: 6-10 weeks. EN 10204 type 3.2 third-party witness: add 1-2 weeks.
Is ASTM B637 magnetic?
No. Magnetic permeability < 1.005 verified per ASTM A342. Compatible with non-magnetic instrumentation, MRI, and electromagnetic-sensitive applications.
Can ASTM B637 be supplied in cold-drawn condition?
Yes — cold-drawn ASTM B637 bar with tighter ±0.05 mm OD tolerance and improved surface finish. Used for precision machined components requiring better dimensional control than hot-rolled bar provides.
What heat-treatment conditions does ASTM B637 cover?
Two primary: solution-treated only (hardness 24-28 HRC, downstream aging by user) and solution-treated + precipitation-aged (hardness 29-32 HRC, ready for use). Customer specifies condition per drawing.
Is ASTM B637 cheaper than AMS 5732?
Yes — typically 10-15 % cheaper due to ISO 9001 industrial QMS vs AMS 5732 AS9100D aerospace AQMS. AMS 5732 includes AS9102 first-article inspection, lot serialization, and aerospace traceability — not required for industrial applications.
Mechanical Properties per This Spec
| Property | Min value (sol+aged) | Notes |
|---|---|---|
| Tensile strength (MPa) | ≥ 895 | Industrial sol+aged |
| Yield strength 0.2 % (MPa) | ≥ 655 | Industrial sol+aged |
| Hardness HRC | 29-32 | Aged target |
A286 Products Manufactured per This Spec
TorqBolt manufactures the following A286 products to this specification:
Mating & Related Specifications
Common mating and related A286 specifications used alongside this spec:
- AMS 5731 / 5732 — Aerospace bar equivalents.
- ASTM A453 grade 660 — Industrial bolting spec.
- UNS S66286 — Underlying chemistry.
Drawing Call-Out Example
A286 bar, ASTM B637, sol-treated and aged, ⌀ 50.0 mm × 3000 mm length, hot-rolled pickled finish, EN 10204 3.1.
Related A286 Specifications & Reference
Other A286 specifications: AMS / ASTM hub · AMS 5525 · AMS 5731 · AMS 5732 · AMS 5737 · AMS 5853 · AMS 5895 · ASTM A453 grade 660 · ASTM A638 grade 660 · ASTM B637 · DIN 1.4980 · UNS S66286.
Canonical A286 reference: A286 chemical composition · A286 mechanical properties · A286 heat treatment · alloy comparisons (vs Inconel 718 · vs Waspaloy).
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