AMS 5732 - A286 (UNS S66286) Bars & Forgings (Solution Heat Treated)
What is AMS 5732?
AMS 5732 is the SAE International aerospace material specification for A286 (UNS S66286), an austenitic precipitation-hardenable iron-nickel-chromium superalloy with additions of molybdenum, titanium, aluminum, boron, and vanadium, supplied in the forms of bars and forgings in the solution heat treated condition.
The nominal composition is 26Ni-15Cr-1.25Mo-2.15Ti-0.20V-0.20Al-0.05C-0.006B (Fe balance).
AMS 5732 specifically provides for ease of forming, cold working, machining, and welding in the as-received solution heat treated condition – the formability and workability emphasis is the key defining characteristic of this specification.
In the solution heat treated condition per AMS 5732, A286 achieves a minimum tensile strength of 130 ksi (896 MPa) and a minimum yield strength of 85 ksi (586 MPa).
AMS 5732 bars and forgings are specified for A286 components that will be subjected to cold forming, cold working, welding fabrication, or precision machining before final customer precipitation aging to service-ready strength.
A286 maintains strength and oxidation resistance at temperatures up to 1,300°F (704°C), and retains its non-magnetic, austenitic structure down to cryogenic temperatures of −320°F (−196°C).
PWA-S-5732 is the Pratt & Whitney Aerospace procurement standard essentially aligned with AMS 5732.
AMS 5732 Available Forms and Stocked Sizes
Primary product form for AMS 5732; supplied in the solution heat treated condition in diameters from 0.1875″ to over 14.000″; stocked in standard lengths with saw-cutting to customer dimension available.
Solution heat treated per AMS 5732; available in custom cross-sections for machining, cold heading, or cold forming into precision hardware and structural components.
Near-net-shape part produced by hot compressive deformation for optimized grain flow; supplied in the solution heat treated condition per AMS 5732 with full CMTRs for subsequent customer cold working, welding, or precipitation aging.
Fighter Jet Metals supplies A286 per AMS 5732 in round bar, flat bar, and forging forms in the solution heat treated condition.
All material is supplied with full certified mill test reports (CMTR) documenting solution heat treatment records, chemical analysis, and mechanical test certifications.
Applications of AMS 5732
Aerospace & Gas Turbine Applications
- Cold-headed fasteners, bolts, and studs fabricated from AMS 5732 round bar in the solution heat treated condition before cold forming and subsequent precipitation aging to full service strength
- High-temperature jet engine fasteners produced by cold heading or cold forging from AMS 5732 A286 bar for turbofan, turbojet, turboprop, and turboshaft engine programs
- Welded engine case assemblies, structural engine hardware, and fabricated engine components requiring A286 bars in the SHT condition for welding before final aging
- Turbine engine structural components machined from AMS 5732 bars in the SHT condition to final geometry before customer precipitation aging
- Aircraft engine hardware and high-temperature fasteners for both commercial and military programs where forming, cold working, or weld fabrication is performed before final aging
- A286 bar stock for cold-formed precision aerospace components requiring non-magnetic, high-temperature performance
Industrial and Energy Applications
- Industrial gas turbine (IGT) fasteners and bolts cold-formed from AMS 5732 A286 bar in the SHT condition for land-based power generation applications
- Welded A286 assemblies for oil and gas applications requiring non-magnetic, corrosion-resistant, high-temperature performance
- Cold-worked A286 bar components for industrial turbomachinery applications requiring post-forming precipitation aging
- Cryogenic structural components requiring non-magnetic behavior down to -320°F (-196°C), fabricated from AMS 5732 bars in the SHT condition
Defense Applications
- Military aircraft engine high-temperature fasteners and bolts cold-headed from AMS 5732 bar in the solution treated condition for subsequent aging to service-ready strength
- Defense engine structural forgings and shaft components requiring AMS 5732 for cold working or forming before final heat treatment
- Turbine engine fastener hardware for fighter aircraft and military rotorcraft requiring full AS9100D-traceable A286 bar supply in the SHT condition
- High-temperature fasteners and welded structural components for military engine programs where A286’s non-magnetic property is a design requirement and cold forming or welding is part of the fabrication process
Chemical Composition - AMS 5732
The following chemical composition limits apply to A286 (UNS S66286) per AMS 5732:
| Element | Symbol | Minimum % | Maximum % |
|---|---|---|---|
| Iron | Fe | - | Balance |
| Nickel | Ni | 24.0 | 27.0 |
| Chromium | Cr | 13.5 | 16.0 |
| Boron | B | 0.003 | 0.010 |
| Molybdenum | Mo | 1.00 | 1.50 |
| Vanadium | V | 0.10 | 0.50 |
| Titanium | Ti | 1.90 | 2.35 |
| Aluminum | Al | - | 0.35 |
| Phosphorus | P | - | 0.030 |
| Carbon | C | - | 0.08 |
| Manganese | Mn | - | 2.00 |
| Silicon | Si | - | 1.00 |
| Copper | Cu | - | 0.50 |
| Sulfur | S | - | 0.020 |
Nickel (24.0–27.0%) is the primary matrix element that provides the austenitic face-centered cubic structure, stable from cryogenic temperatures to the alloy’s service limit.
The high nickel content combined with chromium gives A286 its characteristic non-magnetic behavior in all conditions, making it suitable for applications where magnetic permeability must be controlled.
Chromium (13.5–16.0%) provides oxidation resistance and hot corrosion resistance in gas turbine environments; the nominal 15% chromium level provides corrosion protection without requiring additional coatings for most aerospace applications up to 1,300°F (704°C).
Molybdenum (1.00–1.50%) contributes solid-solution strengthening of the iron-nickel-chromium matrix and improves pitting corrosion resistance.
Titanium (1.90–2.35%) is the primary precipitation hardening element: during customer aging, titanium reacts with nickel to form coherent gamma-prime (γ’) precipitates (Ni₃Ti-based) that are the dominant strengthening mechanism in A286.
In the solution heat treated condition per AMS 5732, all titanium is held in solid solution, which is what gives the alloy its exceptional cold workability and weldability before aging.
Vanadium (0.10–0.50%) improves notch sensitivity and fatigue resistance.
Boron (0.003–0.010%) and Aluminum (max 0.35%) are grain boundary strengtheners that improve stress rupture life and elevated-temperature creep resistance. Iron is the balance element; the high iron content gives A286 a density similar to stainless steel (0.286 lb/in³ / 7.92 g/cm³), significantly lower than nickel-based superalloys – a weight advantage in fastener and fabricated aerospace component applications.
Mechanical Properties - AMS 5732
Minimum mechanical properties for A286 per AMS 5732 in the solution heat treated (SHT) condition:
| Property | Imperial | Metric |
|---|---|---|
| Tensile Strength (min) | 130,000 psi (130 ksi) | 896 MPa |
| Yield Strength, 0.2% offset (min) | 85,000 psi (85 ksi) | 586 MPa |
| Elongation in 2 in. or 4D (min) | 25% | 25% |
| Reduction in Area (min) | 25% | 25% |
Elevated Temperature Properties - AMS 5732
The following elevated temperature properties are for A286 (UNS S66286) in the precipitation aged condition after starting from the AMS 5732 solution heat treated condition.
These are representative typical values from published literature (Carpenter Technology / Special Metals Technical Data):
| Temperature | Tensile Strength (typical) | Yield Strength (typical) | Elongation (typical) |
|---|---|---|---|
| Room Temp (70°F / 21°C) | 145 ksi (1000 MPa) | 100 ksi (690 MPa) | 22% |
| 400°F (204°C) | 140 ksi (965 MPa) | 98 ksi (676 MPa) | 20% |
| 800°F (427°C) | 135 ksi (931 MPa) | 97 ksi (669 MPa) | 18% |
| 1000°F (538°C) | 130 ksi (896 MPa) | 93 ksi (641 MPa) | 17% |
| 1200°F (649°C) | 110 ksi (758 MPa) | 84 ksi (579 MPa) | 16% |
| 1300°F (704°C) | 82 ksi (565 MPa) | 64 ksi (441 MPa) | 18% |
Physical Properties - AMS 5732
| Property | Value (Imperial) | Value (Metric) |
|---|---|---|
| Density | 0.286 lb/in³ | 7.92 g/cm³ |
| Solidus Temperature | ~2500°F | ~1371°C |
| Liquidus Temperature | ~2540°F | ~1393°C |
| Modulus of Elasticity | 29.1 × 10⁶ psi | 201 GPa |
| Thermal Conductivity | 6.8 BTU/(hr·ft·°F) | 11.8 W/(m·K) |
| Thermal Conductivity (1200°F) | 9.2 BTU/(hr·ft·°F) | 15.9 W/(m·K) |
| Coefficient of Thermal Expansion | 9.2 × 10⁻⁶ /°F | 16.6 × 10⁻⁶ /°C |
| Specific Heat | 0.110 BTU/(lb·°F) | 460 J/(kg·K) |
| Max Service Temperature (Rotating Load) | 1300°F | 704°C |
| Max Service Temperature (Static / Structural) | 1500°F | 816°C |
| Solution Heat Treatment Temperature | 1800°F (980°C) / 1 hr min | - |
| Magnetic Permeability | Non-magnetic (austenitic) | - |
AMS 5732 vs AMS 5731 vs AMS 5726 - Which Specification Do You Need?
All three are SAE AMS specifications for A286 (UNS S66286) bars and forgings, but they differ in solution heat treatment parameters, intended processing sequences, and specific requirements. The applicable specification for a given part is governed by the OEM engineering drawing or purchase order:
| Feature | AMS 5726 | AMS 5731 | AMS 5732 |
|---|---|---|---|
| Alloy | A286 (UNS S66286) | A286 (UNS S66286) | A286 (UNS S66286) |
| Product Forms | Bars, Forgings | Bars, Forgings | Bars, Forgings |
| Condition | Solution Heat Treated | Solution Heat Treated | Solution Heat Treated |
| Tensile Strength (min SHT) | 130 ksi (896 MPa) | See current revision | See current revision |
| Yield Strength (min SHT) | 85 ksi (586 MPa) | See current revision | See current revision |
| SHT Temperature | Per spec (consult current revision) | 1800°F (980°C) / 1 hr min | Per spec (consult current revision) |
| Key Characteristic | Consumable electrode melt + SHT - standard procuring specification for A286 bars and forgings with full melt traceability | Standard A286 SHT specification with specific 1800°F (980°C) solution temperature requirement | SHT condition with specific emphasis on formability, cold workability, machinability, and weldability in the as-supplied condition |
| Typical Application | High-temperature fasteners, turbine engine bolts, structural forgings requiring melt traceability | Engine hardware, turbine components, and structural parts requiring the standard A286 SHT condition | Fabricated assemblies, weldments, and parts where forming, cold working, or welding will be performed on the as-received bars or forgings |
Specify AMS 5732 when the OEM drawing calls out AMS 5732 or when procuring A286 bars and forgings for cold heading, cold forming, welding fabrication, or any downstream process where maximum SHT-condition formability and weldability is the priority.
Specify AMS 5731 when the drawing requires the specific 1800°F (980°C) solution heat treatment temperature.
Specify AMS 5726 when the drawing requires consumable electrode melt traceability documented on the CMTR.
Always confirm the specification number on the engineering drawing before procurement – do not substitute one A286 SHT spec for another without engineering approval.
Approved Mill Producers
Fighter Jet Metals sources A286 per AMS 5732 bars and forgings from AS9100D-certified mill producers.
All material is supplied with full certified mill test reports (CMTR), heat/lot numbers, chemical analysis reports (spectrographic), and mechanical test certifications traceable to the originating mill heat and solution heat treatment.
AMS 5732 Machining Guidelines
A286 per AMS 5732 is supplied in the solution heat treated condition, which provides the best machinability of any A286 procurement condition.
The SHT condition delivers lower hardness, higher ductility, and reduced tendency to work-harden rapidly compared to cold-worked (AMS 5853) or aged material.
This is consistent with AMS 5732’s intended procurement purpose: bars and forgings procured for downstream cold working, forming, or welding operations require the softest, most workable starting condition.
For complex fastener heads, precision turned parts, thread-rolled features, and cold-formed components, procuring to AMS 5732 (SHT) and machining or cold working before precipitation aging is the standard preferred sequence.
Key machining considerations for AMS 5732 bars and forgings in the solution heat treated condition:
- Work hardening: A286 in the SHT condition work-hardens more rapidly than standard austenitic stainless steels (304, 316) but more slowly than precipitation hardened or cold-worked condition (AMS 5853). Continuous cutting with no dwell is required to prevent work-hardening ahead of the tool
- Turning and boring: Positive-rake carbide tooling (C2 or C3 carbide, PVD TiAlN coated) recommended; rigid setup required; speeds of 100–200 SFM with flood coolant
- Thread machining: Thread rolling is strongly preferred over thread cutting for AMS 5732 bolt and fastener manufacturing – roll threading in the SHT condition, then precipitation age to produce the specified tensile strength on the finished fastener
- Drilling: High-speed steel drills acceptable for small diameters; cobalt HSS or solid carbide drills recommended for diameters above 0.25″; peck drilling with flood coolant
- Milling: Climbing (down) milling preferred to prevent work-hardening at the cut surface; positive-rake carbide endmills; feed rates high enough to maintain chip load and avoid rubbing
- Cold forming / cold heading: AMS 5732 SHT condition bars are the preferred starting form for cold heading fasteners; the fully recrystallized microstructure provides maximum cold-reduction capacity before cracking
- Coolant: High-pressure flood coolant required at all times; sulfurized or chlorinated cutting oils for difficult features (deep holes, thread cutting)
- Chip control: A286 SHT produces long, stringy chips – chip breaker geometry essential in turning operations; built-up edge formation is the primary tool failure mode
Weldability of AMS 5732
A286 per AMS 5732 is supplied in the solution heat treated (unaged) condition and is weldable in this delivery state.
Because the material has not been precipitation aged, the risk of strain-age cracking (SAC) in the heat-affected zone is significantly lower than for aged material.
AMS 5732’s formability and weldability emphasis makes it the natural procurement choice for A286 components that require welding as part of the fabrication process before final aging:
- TIG (GTAW): Primary welding process for AMS 5732 A286 bars and forgings in the SHT condition; minimum heat input; argon shielding gas; filler metal AMS 5798 (A286-type filler, ER CRNI-2 equivalent) recommended
- Electron Beam (EBW): Used in precision aerospace applications requiring minimal heat input and narrow heat-affected zone; performed in vacuum for contamination control
- Preheat: Preheat is generally not required for thin sections; for thick bar or forging sections (>0.5″), a preheat of 200–300°F (93–149°C) and controlled interpass temperature reduces thermal gradient cracking risk
- Post-weld heat treatment (PWHT): For weldments requiring full precipitation hardened properties, a complete precipitation aging cycle (1325°F / 718°C / 16 hours minimum / air cool) is applied after welding and before final inspection
- Recommended fabrication sequence: Machine all features in SHT condition (AMS 5732) → cold form or weld as required → inspect weld quality → precipitation age to service properties → finish machine and final inspect
- Contrast with aged condition: A286 that has been precipitation aged has significantly higher SAC susceptibility than AMS 5732 SHT material. Weldment repair on aged A286 hardware requires careful procedure qualification and typically re-solution treatment before welding if the part geometry permits
- Why AMS 5732 for welded assemblies: The specific formability and weldability language in AMS 5732 makes it the procurement-of-record for aerospace programs where the bar or forging will be welded before final aging. This is the intended use case that distinguishes AMS 5732 from AMS 5731
Melt Practice - AMS 5732
AMS 5732 covers A286 (UNS S66286) bars and forgings in the solution heat treated condition.
Unlike AMS 5726, which explicitly requires consumable electrode melting (VIM+VAR) and mandates that this melt practice be documented on the certified mill test report (CMTR), AMS 5732 does not impose a consumable electrode melt requirement.
This distinction is important for procurement: when an OEM drawing requires documented consumable electrode melt traceability, AMS 5726 is the applicable specification; when the drawing calls out AMS 5732, the absence of a consumable electrode requirement means a broader range of mill practices may be acceptable, subject to the chemistry and mechanical property requirements of the specification.
The solution heat treatment that defines the as-supplied condition of AMS 5732 dissolves all precipitate phases, fully recrystallizes the microstructure, and places titanium, boron, and vanadium back into solid solution – establishing the alloy in its maximum-ductility, maximum-formability, and maximum-weldability condition.
This is the intended delivery state for AMS 5732: the customer receives bars or forgings in the softest, most workable condition of the A286 alloy, ready for:
- Cold forming and cold heading : The fully recrystallized, precipitation-free microstructure provides the highest possible elongation and reduction in area for cold-working operations
- Welding: Unaged A286 has significantly lower strain-age cracking susceptibility than aged material; AMS 5732 SHT bars and forgings are suitable for fusion welding without the pre-weld re-solution treatment required for aged product
- Precision machining: The SHT condition provides optimal chip formation and surface finish in turning, milling, drilling, and thread-rolling operations before final aging
- Cold working / work strengthening: For applications requiring higher as-worked strength before aging, AMS 5732 SHT bar can be cold worked by the customer to increase strength (see AMS 5853 for pre-cold-worked product)
The emphasis on formability and weldability as the defining procurement purpose is what differentiates AMS 5732 from AMS 5731. Both specifications cover A286 bars and forgings in the solution heat treated condition; the distinction lies in AMS 5732’s specific orientation toward downstream cold working and fabrication processing.
Always confirm the solution heat treatment cycle and chemistry on the certified mill test report before procurement. Verify melt practice documentation requirements against the specific OEM engineering drawing.
AMS 5732 Cross-Reference Specifications
SHEET & PLATE
A286 flat-rolled specifications covering sheet, strip, and plate product forms – the flat-product counterparts to AMS 5732 bars and forgings.
BARS & FORGINGS
A286 bar and forging specifications in various heat treat conditions — the sibling specifications to AMS 5732 for different melt practice, heat treatment parameters, or post-processing requirements.
GE SPECIFICATIONS
GE Aviation quality and material procurement specifications covering A286 product forms used in GE-designed aircraft engine programs.
ROLLS ROYCE SPECIFICATIONS
Certified to Rolls-Royce standards for turbine and high-temperature parts.
PRATT & WHITNEY SPECIFICATIONS
Engineered for Pratt & Whitney engine and structural applications.
SAFRAN SPECIFICATIONS
Manufacturer-specific superalloy components for aerospace applications.
Trade Names and Equivalent Designations
A286 per AMS 5731 is known by the following trade names and equivalent designations across different standards systems:
| Designation | System | Notes |
|---|---|---|
| A-286 / A286 | Common name | Widely used commercial designation; the hyphen is optional |
| Iron Alloy S66286 | Generic name | Generic iron-based superalloy designation for non-proprietary procurement |
| AISI 660 | AISI | designation sometimes used for A286 in commercial sourcing |
| ASTM A638 Gr. 660 | ASTM specification | Precipitation-hardening iron-base superalloy bars, forgings, and rings - includes UNS S66286 (Grade 660) |
| AMS 5726 | SAE AMS | Solution heat treated bars and forgings |
| UNS S66286 | UNS (Unified Numbering System) | Standard material identifier in North America |
| DIN 1.4980 / W.Nr. 1.4980 | Werkstoff Nr. (German) | European material number designation |
| AMS 5731 | SAE AMS | Solution heat treated bars and forgings - 1800°F SHT, related specification |
| AMS 5732 | SAE AMS | Solution-strengthened bars and forgings |
| AMS 5525 | SAE AMS | Solution heat treated sheet, strip, and plate |
| AMS 5853 | SAE AMS | Cold-worked and work-strengthened bars and wire |
| PWA-S-5732 | Pratt & Whitney | P&W equivalent of AMS 5732 |
Why Source AMS 5732 from Fighter Jet Metals?
Full mill certifications on every order
Heat number, lot number, chemical analysis, and mechanical test reports included with every shipment
Complete heat-lot traceability
Full chain-of-custody documentation from mill to your door
Consumable electrode melt traceability
HT cycle documented on every CMTR; AMS 5732 solution-strengthened condition confirmed and traceable from mill to your door
AS9100D-certified aerospace sourcing
Material sourced from AS9100D-certified mills only
OEM specification support
Stock and supply to GE B50T1181C, B50T12, B50T81, MSRR 6531/6532/6688, PWA-S-5732, and DMD 0274-22 requirements in addition to AMS 5731 and related AMS 5525, 5726, 5732, 5734, 5737, 5853, and 5895 specifications
In-house processing
Bar saw cutting to length, trepanning (hollow bar), lathe work (turning), and shearing available; custom-cut sizes to your dimensions
PWA-S-5732 compliant supply
AMS 5732 bars supplied to Pratt & Whitney LCS standards for PWA-S-5732 programs in addition to standard AMS 5732 procurement
Same-day quote response
Competitive pricing with rapid quote turnaround
Certified Material for Critical Service
Materials supplied in 6Al-4V titanium must meet strict aerospace certification and traceability requirements. Fighter Jet Metals supports sourcing across a wide range of AMS, MIL, and OEM specifications, ensuring compliance with industry standards.
All material is supplied with full mill certifications, complete heat-lot traceability, and detailed documentation. This ensures reliability and suitability for safety-critical aerospace, defense, and high-performance engineering applications.