Hastelloy Material: Grades, Composition & Types

Hastelloy material is a nickel-based superalloy family known for outstanding corrosion resistance in the world’s most aggressive chemical and marine environments. Hastelloy is a unique family of alloys combining high strength, heat resistance, and corrosion resistance, making it ideal for applications such as chemical processing equipment, marine and offshore equipment, and aerospace applications. In this guide, we’ll look at what is Hastelloy, its chemical composition, its physical and mechanical properties, the grades of Hastelloy such as C-22, C-276, C-4, B-2, and Hastelloy X, as well as the industries and applications in which it is used. Additionally, we will compare Hastelloy vs Inconel vs Stainless Steel, highlight the main benefits, and review the main cons, and then review any applicable material standards. 

What is Hastelloy Material?

Hastelloy is the trade name for one of a group of high-performance nickel-based alloys that contains nickel (Ni) as the base element, in conjunction with significant amounts of molybdenum (Mo) and chromium (Cr). The Hastelloy alloys are referred to as superalloys due to their retention of engineering properties at elevated temperatures and resistance to corrosion. Haynes International developed the original Hastelloy (Hastelloy is a registered trademark of Haynes International) and has created many grades of Hastelloy for specific environments. For example, the Hastelloy material is designed to withstand very corrosive media (i.e., hot acids, chlorides, seawater) while maintaining a degree of integrity when exposed to high heat and stress. In other words, Hastelloy is a basic alloy of material choice for important equipment, such as chemical plants, oil & gas refineries, marine vessels, and aerospace engines.

Elemental Roles in Hastelloy Composition

Popular Hastelloy Grades: Nominal Chemistry & Key Features

Selection Note: Hastelloy C-22 and Hastelloy C-276 balance Ni-Cr-Mo-W for resistance across mixed oxidizing/reducing environments. Hastelloy B-2 maximizes Mo for pure reducing service (e.g., HCl) but should be avoided where oxidizers are present. Align the grade with your dominant service chemistry and temperature.

Physical Properties of Hastelloy Material

Hastelloy material shows stable behavior at heat, good dimensional control, and useful non-magnetic characteristics. The values below are representative; exact numbers vary by grade and product form.

Mechanical Properties of Hastelloy Material

In solution-annealed condition, Hastelloy material combines high strength with good ductility. Values below are typical for common grades like C-276; verify per heat and form.

Notes: Values vary by grade, heat, and product form. Hastelloy material is usually used annealed for maximum corrosion resistance. Strength and hardness can be increased by cold work; certain specialized grades may respond to age hardening. As a superalloy family, Hastelloys also provide good creep and fatigue resistance, supporting long life under high stress and temperature.

Grades of Hastelloy Material (Condensed)

Hastelloy material spans multiple grades tuned for specific chemistries and temperatures. Use C-series for broad, mixed corrosion; use B-series for pure reducing acids.

Notes for selection:

• Hastelloy C family (C-22, C-276, C-4) handles mixed/unknown chemistries; C-22 skews stronger in oxidizers, C-276 is the broadest generalist, C-4 adds weld/thermal stability.
• B-2 is best only for pure reducing environments; avoid where oxidizing impurities may be present.
• Other options: Hastelloy G-series (phosphoric/wet-process acids) and Hastelloy N (nuclear/molten-salt) for niche use cases.

Hastelloy Density

Hastelloy density typically ranges 8.6–8.9 g/cm³ (e.g., Hastelloy C-22 ≈ 8.69 g/cm³, Hastelloy C-276 ≈ 8.89 g/cm³), noticeably higher than stainless (7.8 g/cm³) and carbon steel (7.85 g/cm³). The added mass comes from heavy alloying (Ni, Mo, W) and must be justified by performance in service.

Why Does it Matter in Design?

• Weight considerations: In aerospace/transport, a Hastelloy material vessel will be heavier than a stainless equivalent; size supports and factor fuel/handling.
• Structural support: Heavier systems increase loads on hangers, skids, and foundations; allow for higher Hastelloy density in calculations.
• Rotating parts: Greater mass raises inertia/centrifugal forces; rarely used for large blades, and if used, design margins must account for it.

Note: Density rises with Mo/W content (e.g., Hastelloy B can be 9.2 g/cc), while grades with more Fe and less Mo (e.g., Hastelloy X) trend lighter (8.22 g/cc). Despite weight and cost, Hastelloy is often chosen because alternatives won’t survive the environment.

Hastelloy X Hardness and High-Temperature Resistance

Hastelloy X hardness in the solution-annealed condition is typically 87–90 HRB (~200 HB), with many specs capped at ≤ 241 HB to preserve toughness. It can be cold-worked to increase hardness yet remains machinable and sufficiently ductile for fabrication.

High-temperature performance: Hastelloy X couples strength with oxidation resistance up to ~1200 °C (2200 °F). Its Ni-Cr-Mo-Fe chemistry (≈22% Cr, 18% Fe, ~9% Mo, minor Co) forms a protective oxide and resists scaling, allowing continuous hot-zone service without excessive softening.

Typical uses: Aerospace and turbine hot sections—combustion chambers, turbine exhaust, afterburner components, furnace hardware—where thermal cycling and flame exposure demand reliable high-temperature resistance.

Bottom line: The balanced Hastelloy X hardness plus exceptional heat stability makes Hastelloy X a first-line choice for high-heat components that few metals can endure.

Types of Hastelloy Material Products

Hastelloy materials can be manufactured into virtually all standard product forms used in industry. At Kalpataru Piping Solutions, as a leading supplier, we provide Hastelloy in many forms to meet diverse project needs:

• Pipes & Tubes: Seamless and welded Hastelloy pipes, tubes, and tubing for chemical process lines, heat exchanger tubing, and offshore umbilicals. The material resists internal acid attack and external seawater corrosion.
• Sheets & Plates: Hastelloy sheets, plates, and coils for reactors, tank linings, flue gas scrubber linings, and pressure vessels. For example, Hastelloy C-276 plates can be rolled into reactor shells. Cut to size is available.
• Fittings & Flanges: A complete range of Hastelloy buttweld fittings such as elbows, tees, reducers, and caps, and flanges including WN, SO, and BL. Using Hastelloy fittings keeps the entire flow path corrosion resistant, which is critical in acid piping networks.
• Valves & Fasteners: High performance Hastelloy valves including ball, gate, and check types, and Hastelloy fasteners such as nuts, bolts, and studs for aggressive media. Ideal for flange bolting in chlorine and chloride bearing services.
• Custom Fabrications: Made to print Hastelloy fabrications including lined vessels, flexible hoses, expansion bellows, spray nozzles, filters, and instrumentation fittings.

By offering all these product types, we serve as a one-stop source for Hastelloy materials. This is important because when a project is using Hastelloy, it often needs multiple components (tubing, flanges, etc.) all in that alloy to maintain consistent performance. Kalpataru’s inventory and network ensure that whether you need a few feet of Hastelloy tubing or a set of Hastelloy valves and fittings, we can deliver certified, high-quality alloy to keep your system uniformly robust.

(Each Hastelloy product comes with material test reports and certifications per relevant ASTM/ASME standards, assuring you of the quality and traceability of the alloy in your project.)

Hastelloy C: Its Unique Properties

Hastelloy C is an early Ni Cr Mo superalloy and the prototype for the C-family. The UNS N10002 formulation had about 15 – 17% Mo, ~15% Cr in a nickel continuum and displayed unique resistance to oxidizing and reducing acids. It performed well in sulfuric, phosphoric and chlorine contaminated acids, and had greater resistance to chloride stress corrosion cracking than stainless, so it was popular for chemical reactors, evaporators, and transfer piping. 

The key properties are representative of the C family. Density ~8.7 – 8.9 g/cm³, usually non magnetic, melting point range ~1325 – 1370°C, lower thermal expansion than typical stainless, modicum of conductivity.  In the solution annealed condition hardness ~88-96 HRB, tensile strength ~ 690-785 MPa, yield strength ~ 280-355 MPa, elongation ~40-50 percent. Some welding sensitivities showed in the original grade and Hastelloy C 276 had lower C and Si with a small W addition for acceptable as welded service, and Hastelloy C 22 had higher Cr for better performance in oxidizing media. In practice selection tends to favor Hastelloy C 276 for broader resistance and Hastelloy C 22 when oxidizers predominate.

The Importance of Hastelloy C 276 in Modern Industries

Hastelloy C 276 is a versatile corrosion resistant alloy for mixed chemical service. It resists pitting, crevice corrosion and stress corrosion cracking in oxidizing and reducing environments, including chlorides and chlorine compounds, making it the automatic default upgrade when stainless or standard nickel alloys are marginal.

Hastelloy C 276 is used in industries in chemical reactors, columns, exchangers, and piping, in flue gas desulfurization scrubbers and ducts, in sour oil and gas service, and in pharmaceutical or biotech facilities which use different process acids alternatively with chlorine based cleaning. It was designed for as welded use with standard nickel alloy fillers and is commercially available in typical product forms.

In summary, Hastelloy C 276 continues to be the gold standard when reliability is non-negotiable, offering a wide resistance profile along with proven fabrication and supply to decrease the risk of leaks, contamination, and unplanned downtime.

Applications of Hastelloy Material in Different Industries

Because of its formidable properties, Hastelloy finds use in a spectrum of industries where ordinary metals falter. Here are some key industries and how they leverage Hastelloy alloys:

• Chemical Processing: Hastelloy material is widely used for reactors, pressure vessels, columns, heat exchangers, piping and pumps where strong acids, chlorinated organics and mixed media are present. It handles hot contaminated acids and chlorides, and Hastelloy linings or claddings protect steel equipment in fertilizer and acid plants.
• Marine Industry: In seawater, brine and salt spray, alloys like Hastelloy C-276 and Hastelloy C-22 resist pitting and crevice attack better than stainless 316. Typical uses include seawater cooling systems, marine scrubbers, desalination units, heat exchanger tubing, and submerged components such as pump shafts, valve trim and fasteners.
• Pollution Control: Flue Gas Desulfurization systems use Hastelloy for scrubber tower internals, slurry piping and mist eliminators exposed to hot acidic and chloride rich liquids. Waste incineration and water treatment lines may specify Hastelloy for heat recovery boilers, stack liners and chlorine or ozone facing parts.
• Power Generation: In nuclear and geothermal service, Hastelloy withstands nitric acid and corrosive brines where standard alloys fail. Hastelloy X is common in gas turbine hot sections, while Hastelloy N and Hastelloy C-276 appear in molten salt, reprocessing and other demanding circuits.
• Aerospace: Hastelloy alloys serve in engine hot zones, exhaust systems and fuel system components where heat and corrosion coincide. Applications include combustion chambers, turbine exhaust parts and hardware that sees thermal cycling and aggressive gases.

Across these sectors, Hastelloy material is selected when operating conditions exceed the capability of conventional metals. Although premium in cost, its long service life and reliability in extreme media often deliver lower life cycle risk and fewer shutdowns.

Hastelloy vs Inconel vs Stainless Steel: Key Differences

When comparing Hastelloy with other high-performance alloys like Inconel or common stainless steels, several important differences emerge in terms of composition, corrosion resistance, temperature capability, and cost. Here’s a breakdown of Hastelloy vs Inconel vs Stainless Steel:

Example comparison (quick reference)

Advantages of Hastelloy Material

Hastelloy alloys come with several distinct advantages that make them attractive for critical applications:

• Unmatched corrosion resistance: Hastelloy materials provide an outstanding level of corrosion resistance in boiling acids, seawater, wet chlorine gas, organic acids. They resist uniform corrosion as well as pitting, crevice corrosion, and stress-corrosion cracking, resulting in extended service life and less unplanned downtime.
• High strength and durability: Solid-solution strengthened nickel chemistry give many Hastelloy grades tensile strengths around ~700 MPa and retain strength with heat and chemicals to limit creep and retain toughness under pressure and high-temperature use.
• Thermal stability: Hastelloy alloys display stable behaviors at temperature by virtue of low thermal expansion and strong oxidation resistance (particularly in Cr-bearing grades). Hastelloy X remains stable and strong until ~1200 °C for furnace and aerospace duty.
• Weldability and fabrication: Most grades of Hastelloy weld with available TIG/MIG methods and typically have no post-weld heat treatment (PWHT) requirements to restore corrosion resistance. They also can be formed (forging, cold-rolling, deep-drawing) making complicated vessels and thin-wall tubing possible.
• Non-magnetic: The austenitic Ni matrix, in general, makes Hastelloy material non-magnetic, which is beneficial around MRI, precision instruments and naval equipment where magnetic interference (e.g., gauss meters) can be a problem.
• Life-cycle and longevity of use: Even though higher in price, Hastelloy more often than not will last longer than stainless steel by an order of magnitude in harsh media, reducing replacements and shutdowns and improved overall cost of ownership.

Limitations of Hastelloy Material

Despite all its superb qualities, Hastelloy is not a magic solution for every problem. There are some limitations and challenges to consider:

• High cost: Nickel, molybdenum, cobalt, and tungsten content make Hastelloy significantly more expensive than stainless or carbon steel and usually reserved for corrosion risk. 

• Difficult machining and complicated fabrication: Hastelloy material work hardens, require sharp tooling, slow speeds, and robust set-ups, and tool wear is high; caution with cutting tools welcomed. With welding, tight control on heat input must be achieved through a manipulated factor due to its low thermal conductivity.

• Limited availability and longer lead times: Specialty supply chains and limited producers could lead to longer lead times for Hastelloy material and limited sizes. You planning will be critical, particularly with grades that have long lead times, e.g., B-3, or C-2000.

• Not indestructible: Even Hastelloy may not be impervious – stress corrosion cracking in specific hot caustics, high velocity solids could cause erosion, and localized attack could ensue from improper heat treat can all happen, thus essential to make sure the correct grade is selected and design is sound.

• Mechanical considerations: Although strength is developed as an attractive trait, most grades are not without necessarily optimizing extreme high temperature structural strength (that`s the only capability in Inconel) and higher density of Hastelloy also creates more weight in the final component.

Material Codes & Standards of Hastelloy

Specifying the right Material Codes & Standards of Hastelloy ensures the alloy’s composition, properties, and quality are consistent across suppliers and forms. Use formal identifiers like UNS, ASTM/ASME, and DIN/EN (Werkstoffnummer) in all purchase orders, and insist on traceable documentation such as an EN 10204 3.1 or 3.2 certificate and a Mill Test Report (MTR).

Supplier Note: At Kalpataru Piping Solutions, we supply Hastelloy to the relevant UNS, ASTM/ASME, and DIN/EN requirements and provide full documentation, including EN 10204 3.1 or 3.2 and the Mill Test Report (MTR), for Hastelloy pipes per ASTM B622, Hastelloy fittings per ASTM B366, and Hastelloy plate per ASTM B575.

Conclusion

Hastelloy is the family of nickel-based superalloys that have a chemistry of Ni-Mo-Cr that provides excellent corrosion resistance and reliable performance at temperature.  Engineers can obtain reliability and long service life in severely hostile environments, involving harsh acids, seawater, chlorides, and hot gases, with grades such as Hastelloy C-276, Hastelloy C-22, Hastelloy B-2, and Hastelloy X. 

Whether it’s chemical reactors, heat exchangers, marine systems, flue-gas scrubbers or aerospace hot sections, Hastelloy alloys can be relied on to help keep critical processes safe when standard materials will not survive.  There is consideration of cost and fabrication challenges, but by using the correct grade and relevant standards, engineers maximize the value of life-cycle cost.

Kalpataru Piping Solutions is pleased to be a supplier of Hastelloy pipes, tubes, fittings, flanges and more.  We consider that our specialty in these alloys allows us to assist clients to implement Hastelloy in whatever work they do, from grade selection to supplying quality certified materials, as rapidly and as reliably as possible.  If your next project requires the ultimate corrosion resistance and durability, reach out to our team.

Contact us today to source high-quality Hastelloy materials for your next project, and let our experience ensure your process is a lasting success. Our goal is to provide you the materials that outlast and outperform, so you can focus on innovation and production without worry.