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Hastelloy X vs C-276 vs Haynes 282 —
Properties, Specifications, and How to Choose
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Beyond
Inconel 625 and 718, which we cover in a separate article, the nickel superalloy family includes several other grades that engineers encounter in high-temperature and severe-corrosion applications. This guide covers three of the most commonly specified: Hastelloy X (oxidation resistance at extreme temperature), Hastelloy C-276 (universal corrosion resistance), and Haynes 282 (high creep strength with excellent weldability). All three are nickel-based, all are difficult to machine, and all are expensive. The question is which one your application actually requires. We machine all three here at C&W Manufacturing.
Trademark vs Generic Names
These alloys carry trademarked names that are used interchangeably with generic designations in industry. Understanding which is which prevents specification confusion on drawings and purchase orders.[1]
A note on naming
HASTELLOY® and HAYNES® are both registered trademarks of Haynes International, Inc. On drawings, you can specify either the trademarked name or the UNS designation. For example, "Nickel Alloy Bar, UNS N10276, Annealed, per
AMS 5750" is equivalent to "HASTELLOY® C-276 Bar, Annealed, per
AMS 5750" The UNS number is unambiguous and avoids trademark issues in specifications.
At a Glance — All Three Grades
Hastelloy X and C-276 are solid-solution strengthened and used in the annealed condition only. Haynes 282 is gamma-prime strengthened and must be gamma-age hardenedto reach its full properties.Inconel 718 included as reference.[1][]2][3]
Hastelloy X
UNS N06002 · AMS 5754 (bar) · AMS 5536 (sheet)
"The oxidation grade" — extreme temperature stability
StrengtheningSolid solution
AdvantageOxidation resistance
Hastelloy C-276
UNS N10276 · AMS 5750 (bar) · ASTM B574
"Universal corrosion resistance" — most versatile alloy
StrengtheningSolid solution
AdvantageCorrosion resistance
Haynes 282
UNS N07208 · AMS 5951 (sheet) · AMS 5952 (bar)
"The creep strength grade" — weldable gamma-prime
Elongation20% aged / 59% ann.
StrengtheningGamma-prime (aged)
WeldabilityExcellent (for class)
Heat TreatYes (2-step aging)
AdvantageCreep + weldability
Strength Comparison
Tensile strength at room temperature
316 Stainless (ref)
84 ksi / 579 MPa
Hastelloy X (annealed)
110 ksi / 760 MPa
Hastelloy C-276 (annealed)
115 ksi / 790 MPa
Inconel 625 (ref, annealed)
120 ksi / 827 MPa
Haynes 282 (aged)
170 ksi / 1172 MPa
Inconel 718 (ref, aged AMS 5664)
185 ksi / 1276 MPa
17-4 PH H900 (ref)
190 ksi / 1310 MPa
Property Comparison Chart
Toggle between properties to compare all three grades with reference materials.[1][2][3]
Nickel superalloy comparison
Hastelloy X annealed, C-276 annealed, Haynes 282 aged, with Inconel 718 aged and 316 SS as reference.
Tensile strength
Yield strength
Elongation %
Max service temp (°F)
Grade-by-Grade Breakdown
Hastelloy X (Alloy X, UNS N06002): Oxidation resistance at extreme temperature
Hastelloy X is a nickel-chromium-iron-molybdenum alloy optimized for oxidation resistance at temperatures up to 2200°F (1204°C). It offers the highest useful oxidation temperature of the three alloys covered here, making it the standard material for gas turbine combustion components, furnace fixtures, and afterburner assemblies. Its room-temperature strength is moderate (110 ksi tensile), but its value lies in retaining useful strength and resisting scaling at temperatures that would destroy most other alloys.[1]
Hastelloy X is solid-solution strengthened and used in the annealed condition only. It cannot be precipitation hardened. It has excellent weldability and fabricability, making it a preferred material for complex sheet metal fabrications, welded assemblies, and components that need to be formed before installation in high-temperature service.
Typical components
Gas turbine combustion cans and liners, transition ducts, afterburner components, jet engine tailpipes, furnace rolls and trays, industrial heating elements, petrochemical process equipment, cabin heaters, and spray bars. If the part lives inside a combustion zone or furnace above 1800°F, Hastelloy X is likely the right call.
When to specify Hastelloy X
Specify
AMS 5754 (bar) or
AMS 5536 (sheet/plate) when the part must resist oxidation and retain structural integrity at temperatures above 1800°F (982°C). If the primary driver is wet corrosion resistance rather than dry oxidation resistance, C-276 is the better choice. If you need high mechanical strength at temperature, consider Haynes 282 or
Inconel 718.
Hastelloy C-276 (Alloy C-276, UNS N10276): Universal corrosion resistance
Hastelloy C-276 is a nickel-molybdenum-chromium-tungsten alloy with the broadest corrosion resistance of any commercially available nickel alloy. It resists reducing acids, oxidizing acids, chloride-induced stress corrosion cracking, pitting, crevice corrosion, and a wide range of aggressive chemical environments that would destroy 316 stainless and even Inconel 625. It is one of the few alloys resistant to wet chlorine gas, hypochlorite, and chlorine dioxide.[2]
Like Hastelloy X, C-276 is solid-solution strengthened, used in the annealed condition, and cannot be precipitation hardened. Its room-temperature strength is similar to Hastelloy X (115 ksi tensile). Its service temperature ceiling is lower (1900°F vs 2200°F), but its corrosion resistance is dramatically superior. C-276 has excellent weldability and does not require post-weld heat treatment, making it suitable for chemical process equipment in the as-welded condition.
Typical components
Flue gas desulfurization systems, chemical reactor vessels, heat exchangers for aggressive media, sour gas handling equipment, pharmaceutical processing, pollution control scrubbers, waste treatment systems, pulp and paper bleach plants, and offshore oil and gas components exposed to hydrogen sulfide. If the part lives in an environment that would pit or crack 316 stainless, C-276 is the default upgrade.
When to specify Hastelloy C-276
Specify
AMS 5750 (bar) or
ASTM B575 (plate) when the operating environment involves strong acids, chlorides, wet chlorine, sour gas, or chemical mixtures where no single corrosion mechanism dominates. C-276's "universal" resistance means it handles both oxidizing and reducing environments, unlike most alloys which favor one or the other. Note that C-276 is not optimized for high-temperature oxidation; use Hastelloy X for dry high-temperature service above 1900°F.
Haynes 282 (Alloy 282, UNS N07208): Creep strength with weldability
Haynes 282 is the newest of the three alloys, developed specifically to fill a gap in the superalloy portfolio: high creep strength in the 1200 to 1700°F range (649–927°C) combined with excellent weldability and resistance to strain-age cracking. Most gamma-prime strengthened superalloys in this creep-strength class (like Waspaloy and René 41) are notoriously difficult to weld. Haynes 282 achieves comparable creep performance with a lower volume fraction of gamma-prime, which gives it significantly better fabricability.[3]
Unlike Hastelloy X and C-276, Haynes 282 must be age hardened to reach its full properties. The standard dua-step heat treatment is 1850°F (1010°C) / 2 hours / air cool, diikuti oleh 1450°F (788°C) / 8 hours / air cool. In the annealed condition, its tensile strength is only 122 ksi (839 MPa) with 59% elongation. After aging, it reaches 170 ksi (1172 MPa) with 20% elongation.
Typical components
Gas turbine combustor and transition section fabrications, turbine exhaust nozzles, high-temperature springs, turbocharger seals, advanced ultra-supercritical boiler components, and any hot-gas-path component where creep life at 1200–1700°F is the governing design criterion. Haynes 282 is increasingly specified for next-generation turbine programs where Waspaloy was the previous standard.
When to specify Haynes 282
Specify
AMS 5951 (sheet/plate) or
AMS 5952 (bar) when the part must sustain load under creep conditions in the 1200–1700°F range and the design involves welded fabrication. If weldability is not critical and maximum creep strength is the only concern, Waspaloy or René 41 may also be candidates, but they carry significantly higher fabrication risk. Haynes 282 in the annealed condition (122 ksi tensile) may also serve applications where creep is not governing but moderate high-temperature strength is needed without aging.
When to Choose Each Grade
Each of these three alloys was designed for a different primary challenge. Choosing correctly starts with identifying which challenge governs your design.
Choose Hastelloy X when
The part operates in a high-temperature oxidizing environment above 1800°F. Dry oxidation resistance is the primary requirement. The part is a thin-walled fabrication (combustion liner, transition duct, furnace fixture) that needs to survive thermal cycling without scaling. Moderate room-temperature strength is acceptable because the design is governed by oxidation life, not mechanical load.
Choose Hastelloy C-276 when
The part operates in an aggressive wet corrosion environment involving acids, chlorides, or mixed corrosive media. No single corrosion mechanism dominates (you need resistance to both oxidizing and reducing conditions).
316 stainless atau
Inconel 625 have been evaluated and found insufficient for the specific chemistry. The part needs to be used in the as-welded condition without
post-weld heat treatment.
Choose Haynes 282 when
The design is governed by creep life in the 1200–1700°F range. The component involves welded fabrication and you cannot accept the strain-age cracking risk of Waspaloy or René 41. You need
Inconel 718 level strength but at a higher service temperature (718 is limited to ~1300°F). The part is a structural hot-gas-path component in a turbine engine program.
Full Property Comparison
All values for standard conditions. Inconel 718 (aged, AMS 5664) included as reference since it is the most commonly compared nickel superalloy.[1][2][3][4]
Cost Guidance for Engineers
All three of these alloys are expensive. Material cost alone runs $40–100+/lb depending on the grade, form, and quantity. Machining cost is 5–15× aluminum baseline due to low thermal conductivity and aggressive work hardening. The cost decisions that matter most happen at the drawing stage.
⚠ Before specifying any of these alloys
Ask whether
Inconel 625 (for corrosion) or
17-4 PH stainless (for strength below 300°C) would satisfy the requirement at lower cost. If the operating temperature is below 1200°F and the corrosion environment is moderate, you may not need a superalloy at all. We machine all these materials at C&W and can advise on the most cost-effective material for your specific application.
Haynes 282: annealed may be enough
Haynes 282 in the annealed condition delivers 122 ksi tensile, which exceeds
Inconel 625 and is comparable to
Inconel 718 annealed (150 ksi). If your structural analysis shows the design works at annealed properties and creep is not the governing criterion, eliminating the two-step
aging cycle removes heat treatment cost, eliminates aging distortion, and reduces machining cost significantly. Ask the question before defaulting to the aged condition.
⚠ Engineering Check
Ask if
Inconel 625 or
17-4 PH satisfy your needs at a lower cost before defaulting to these superalloys.
Which Grade Is Right for Your Part?
Hastelloy X
Best for: Extreme oxidation environments
When the part lives in a combustion zone or furnace above 1800°F. Oxidation resistance to 2200°F. Cannot be age hardened. Excellent weldability and formability.
Combustion liners
Transition ducts
Afterburners
Furnace fixtures
Tailpipes
Hastelloy C-276
Best for: Universal corrosion resistance
When the environment is aggressively corrosive and 316 or 625 aren't enough. Resists both oxidizing and reducing acids. As-welded service. Cannot be age hardened.
Flue gas desulfurization
Chemical reactors
Sour gas
Pharma
Pollution control
Haynes 282
Best for: High-temp structural with welding
When creep strength at 1200–1700°F governs the design and the component must be welded. Replaces Waspaloy with better fabricability. Requires aging for full properties.
Turbine combustors
Exhaust nozzles
Hot-gas-path
Turbocharger seals
A-USC boilers
Need help selecting the right nickel superalloy?
We machine Hastelloy X, C-276, Haynes 282, and Inconel regularly. Submit your print for an engineering review.
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