Views: 8 Author: Monica Publish Time: 2026-08-28 Origin: Site
Table of Contents
Hastelloy C276 is a nickel-based corrosion-resistant alloy developed for demanding chemical environments. Its principal engineering advantage is corrosion resistance, but its mechanical properties also make it suitable for pressure-containing and fabricated components.
The alloy is designated UNS N10276 and is commonly associated with W.Nr. 2.4819.
For engineering purposes, the most important Hastelloy C276 mechanical properties include:
Tensile strength
Yield strength
Elongation
Hardness
Density
Ductility
Toughness
Strength retention at elevated temperatures
Low-temperature mechanical performance
For typical solution-annealed wrought C276 material at room temperature, commonly specified minimum tensile strength is approximately 690 MPa (100 ksi), with a minimum yield strength around 283 MPa (41 ksi) and minimum elongation of approximately 40%. Actual requirements depend on product form and the governing material specification.
The key point is that C276 combines useful mechanical strength and ductility with an exceptionally corrosion-resistant nickel alloy matrix.
For the broader material overview, see the Ultimate Guide to Hastelloy C276.
The following values provide a useful general reference for solution-annealed wrought C276 material.
Property | Typical / Specified Value |
|---|---|
UNS designation | N10276 |
Werkstoff No. | 2.4819 |
Density | Approx. 8.89 g/cm³ |
Tensile strength | ≥ 690 MPa (100 ksi) |
Yield strength, 0.2% offset | ≥ 283 MPa (41 ksi) |
Elongation | ≥ 40% |
Elastic modulus | Approx. 205 GPa |
Poisson's ratio | Approx. 0.307 |
Melting range | Approx. 1,325–1,380°C |
Typical condition | Solution annealed |
These values should be treated as general engineering reference data rather than a substitute for the requirements of a specific ASTM, ASME, or project specification.
Product form, thickness, heat treatment, testing method, and applicable standard can all influence the reported mechanical properties.
Tensile strength is the maximum engineering stress that a material can withstand during a tensile test before fracture.
For commonly specified solution-annealed C276 wrought products, a minimum tensile strength of approximately:
690 MPa (100 ksi)
is widely specified.
This provides C276 with sufficient tensile capacity for many demanding chemical-processing components.
However, tensile strength alone should never be used to determine whether a material is suitable for a pressure vessel or piping system.
Engineering design must also account for:
Yield strength
Design temperature
Wall thickness
Pressure
Corrosion allowance
Welding condition
Fatigue
Creep or long-term exposure
Applicable design code
For pressure-containing components, allowable stress rather than ultimate tensile strength is generally the more useful design parameter.
The yield strength indicates the stress at which permanent plastic deformation begins.
For solution-annealed C276, a commonly specified minimum 0.2% offset yield strength is approximately:
283 MPa (41 ksi)
The difference between tensile strength and yield strength is important.
A material can have a high ultimate tensile strength while still allowing substantial plastic deformation before fracture.
C276 combines moderate-to-high yield strength with significant elongation, making it useful where components need both structural capacity and deformation tolerance.
Hastelloy C276 generally exhibits good ductility.
A commonly specified minimum elongation for solution-annealed wrought material is approximately
40%
Elongation is measured during a tensile test and indicates how much the specimen can plastically deform before fracture.
High elongation is valuable during:
Forming
Bending
Fabrication
Pipe and tube processing
Welding
Mechanical loading
Thermal cycling
This ductility is one reason C276 can be fabricated into complex chemical-processing components rather than being restricted to simple structural shapes.
Hardness is another commonly requested mechanical property.
C276 is not normally selected because it is an exceptionally hard alloy. Instead, its value comes from the combination of corrosion resistance, strength, ductility, and fabricability.
Published C276 data commonly report hardness in the range of approximately Rockwell B 80–90, depending on product condition and processing.
Hardness can vary significantly according to:
Cold working
Heat treatment
Product form
Thickness
Manufacturing route
Testing method
Therefore, hardness values should always be evaluated against the applicable product specification.
For machining considerations, see Hastelloy C276 Machining Tips.
Hastelloy C276 has a density of approximately:
8.89 g/cm³
This is higher than the density of many stainless steels.
For comparison, typical density values are approximately:
Material | Approximate Density |
Hastelloy C276 | 8.89 g/cm³ |
316L stainless steel | 8.0 g/cm³ |
904L stainless steel | 8.0 g/cm³ |
Titanium Grade 2 | 4.5 g/cm³ |
Carbon steel | 7.85 g/cm³ |
The relatively high density of C276 is mainly associated with its nickel-rich composition and substantial additions of heavy alloying elements such as molybdenum and tungsten.
This matters when calculating:
Component weight
Transportation cost
Support loads
Equipment dead weight
Material purchasing quantities
The elastic modulus of C276 is approximately 205 GPa at room temperature.
The elastic modulus describes the relationship between stress and elastic strain.
In practical terms, it indicates how much the alloy elastically deforms under an applied load.
For equipment designers, elastic modulus becomes important when evaluating:
Deflection
Buckling
Thermal expansion
Structural stiffness
Vibration
Pressure equipment geometry
C276 should therefore not be evaluated only on tensile strength. The entire mechanical-property profile matters when designing process equipment.
The Poisson's ratio of Hastelloy C276 is commonly reported at approximately:
0.307
Poisson's ratio describes the relationship between longitudinal deformation and transverse deformation when a material is loaded elastically.
Although it is rarely the first property considered by a purchasing engineer, it can be relevant to detailed finite-element analysis and mechanical design calculations.
C276 offers good toughness across a broad temperature range.
This characteristic is important for chemical-processing equipment that may experience:
Thermal cycling
Start-up and shutdown
Pressure fluctuations
Impact loading
Low-temperature service
Welded fabrication
Its nickel-based austenitic matrix contributes to its useful toughness compared with some more brittle corrosion-resistant materials.
For applications involving very low temperatures, however, engineers should verify impact and fracture-toughness requirements against the specific product specification and design code.
One of the useful characteristics of nickel-based alloys is their ability to retain good toughness at low temperatures.
C276 can therefore be considered for certain low-temperature applications where brittle fracture is a concern.
However, "good low-temperature performance" does not mean that every C276 product automatically satisfies every cryogenic design requirement.
The engineer should evaluate:
Minimum design temperature
Impact requirements
Product form
Thickness
Heat treatment
Welding condition
Applicable pressure-vessel or piping code
For critical cryogenic applications, material certification and qualification testing should be based on the project specification.
C276 retains useful mechanical strength at elevated temperatures, but its mechanical properties decrease as temperature rises.
At high temperatures, engineers must consider more than short-term tensile strength.
Long-term exposure may involve:
Creep
Stress relaxation
Microstructural changes
Grain-boundary effects
Oxidation
Corrosion
Phase stability
This is particularly important because C276 is often used in environments where temperature and corrosion occur simultaneously.
An alloy may have adequate tensile strength at a given temperature but still be unsuitable for a particular process because corrosion becomes excessive.
Consequently, high-temperature material selection should consider mechanical performance and corrosion resistance together.
For a dedicated discussion of service temperatures, see Hastelloy C276 Temperature Limits.
The coefficient of thermal expansion of C276 is approximately:
11.2 × 10⁻⁶ m/m·°C
near room temperature, although the value changes with temperature.
Thermal expansion is important in equipment exposed to repeated heating and cooling.
Examples include:
Heat exchangers
Reactors
Process piping
Scrubbers
Chemical tanks
High-temperature process equipment
When C276 is connected to another metal, differences in thermal expansion can generate additional stresses during temperature changes.
Engineers should therefore consider thermal expansion when designing dissimilar-metal joints and restrained piping systems.
C276 has relatively low thermal conductivity compared with carbon steel and copper-based alloys.
A commonly cited room-temperature value is approximately:
10.2 W/m·K
This property matters in heat-transfer equipment.
For example, if C276 is used for a heat-exchanger tube, the alloy's excellent corrosion resistance may be highly desirable, but its relatively low thermal conductivity must also be included in the thermal design.
The actual heat-transfer coefficient of a component depends on much more than material conductivity, including:
Wall thickness
Fluid velocity
Fouling
Surface condition
Fluid properties
Geometry
Temperature difference
Therefore, thermal conductivity should be considered as one parameter within the complete heat-transfer calculation.
Yes. Like many nickel-based alloys, Hastelloy C276 can experience work hardening during cold deformation and machining.
This characteristic is important during manufacturing.
Aggressive or repeated machining can locally harden the surface, potentially making subsequent cutting more difficult.
Machinists therefore commonly use controlled:
Cutting speeds
Feed rates
Depths of cut
Tool geometry
Coolant strategies
This is one reason C276 requires different machining practices from ordinary carbon steel.
For practical production guidance, see Hastelloy C276 Machining Tips.
Cold working can increase strength and hardness while reducing ductility.
The basic relationship is:
More cold work → higher strength and hardness → potentially lower elongation
This can be useful when a component requires higher mechanical strength.
However, cold-worked material may behave differently during forming, welding, and subsequent heat treatment.
For this reason, the material condition should be clearly identified when comparing mechanical-property data.
A solution-annealed C276 plate and a heavily cold-worked C276 component should not be expected to exhibit identical tensile or hardness values.
Hastelloy C276 is commonly supplied in a solution-annealed condition.
Solution annealing is used to produce a controlled metallurgical structure and optimize the combination of corrosion resistance and mechanical properties.
The actual heat-treatment requirements depend on the product specification.
Improper thermal exposure can influence:
Grain structure
Precipitation
Ductility
Strength
Corrosion resistance
This is particularly important for welded or fabricated components.
Heat treatment should therefore follow the applicable material standard and qualified fabrication procedure rather than relying on generic temperature recommendations.
Hastelloy C276 pipe is frequently used in chemical-processing and corrosive-service applications.
For pipe, engineers typically evaluate:
Yield strength
Tensile strength
Elongation
Wall thickness
Design pressure
Design temperature
Corrosion allowance
Manufacturing method
Nondestructive testing
Weld quality
Seamless and welded C276 pipe can have different manufacturing routes and specification requirements.
The mechanical properties must therefore be verified against the applicable ASTM or ASME pipe specification.
For buyers, mechanical properties should never be evaluated separately from corrosion resistance.
A pipe may have sufficient mechanical strength but still be inappropriate if the process chemistry exceeds its corrosion capability.
A common engineering question is whether C276 has stronger mechanical properties than 316L stainless steel.
The answer depends on the specific product condition and temperature.
In many room-temperature comparisons, C276 provides competitive tensile and yield strength while offering a substantially different corrosion-resistance profile.
Property | Hastelloy C276 | 316L Stainless Steel |
Alloy family | Nickel-based | Austenitic stainless steel |
Tensile strength | ≥ ~690 MPa | Commonly ≥ ~485 MPa under many product specifications |
Yield strength | ≥ ~283 MPa | Commonly ≥ ~170 MPa under many product specifications |
Elongation | ≥ ~40% | Commonly ≥ ~40% |
Density | ~8.89 g/cm³ | ~8.0 g/cm³ |
Primary advantage | Severe corrosion resistance | Cost-effective general corrosion resistance |
The comparison should not be interpreted as "C276 is always mechanically superior."
316L remains an excellent engineering material for many applications.
C276 becomes attractive when the corrosive environment, rather than mechanical strength alone, drives material selection.
Both C276 and Inconel 625 are nickel-based alloys, but they are optimized for somewhat different engineering priorities.
Inconel 625 is widely recognized for its combination of:
High strength
Corrosion resistance
Fatigue resistance
Elevated-temperature capability
C276 is particularly known for:
Broad chemical corrosion resistance
Resistance to localized corrosion
Performance in aggressive acid environments
Weldability
Low-carbon chemistry
Therefore, a mechanical-property comparison should always be combined with corrosion and temperature requirements.
For a complete comparison, see Hastelloy C276 vs Inconel 625.
The most important property depends on the application.
For pressure piping
Prioritize:
Yield strength
Tensile strength
Design allowable stress
Elongation
Temperature-dependent properties
Corrosion allowance
For heat exchangers
Prioritize:
Corrosion resistance
Tensile strength
Yield strength
Thermal conductivity
Thermal expansion
Tube-wall requirements
For chemical reactors
Prioritize:
Corrosion resistance
Yield strength
Tensile strength
Weldability
Temperature capability
Thermal cycling behavior
For welded equipment
Prioritize:
Weldability
Ductility
Corrosion resistance after welding
Tensile strength
Yield strength
Heat-treatment condition
This illustrates an important principle:
There is no single "best" mechanical property. Material selection requires balancing mechanical performance with corrosion, temperature, fabrication, and lifecycle requirements.
When selecting C276, engineers should evaluate mechanical properties alongside the actual service environment.
A practical material-selection sequence is:
Process chemistry → Temperature → Corrosion mechanism → Pressure → Mechanical requirements → Fabrication → Applicable standard → Lifecycle cost
This order prevents a common mistake: selecting a material based solely on tensile strength.
For example, a lower-cost stainless steel may provide adequate tensile strength but fail prematurely because of chloride-induced corrosion.
Conversely, selecting C276 solely because it has excellent corrosion resistance may be economically unnecessary for a relatively mild environment.
The optimum material is the one that provides sufficient performance over the required service life.
When purchasing C276, request documentation showing the actual tested properties for the supplied heat and product.
Important documentation can include:
Material Test Certificate (MTC)
Heat number
Chemical analysis
Tensile test results
Yield strength
Elongation
Hardness
Heat-treatment condition
Product specification
Nondestructive examination results
Dimensional inspection
For critical equipment, the purchaser should verify that the supplied material complies with the exact ASTM, ASME, or project specification.
This is particularly important because published datasheet values are not necessarily identical to the contractual acceptance requirements for every product form.
What is the tensile strength of Hastelloy C276?
A commonly specified minimum tensile strength for solution-annealed wrought C276 is approximately 690 MPa (100 ksi). The exact requirement depends on product form and applicable specification.
What is the yield strength of Hastelloy C276?
A commonly specified minimum 0.2% offset yield strength is approximately 283 MPa (41 ksi) for solution-annealed wrought material.
What is the elongation of Hastelloy C276?
A commonly specified minimum elongation is approximately 40% for solution-annealed wrought C276 material.
What is the hardness of Hastelloy C276?
Hardness varies with product condition and processing. Published values commonly fall around the Rockwell B 80–90 range, but the governing product specification should be used for acceptance.
Is Hastelloy C276 a strong alloy?
Yes. C276 provides useful tensile and yield strength combined with good ductility. However, it is primarily selected for corrosion resistance rather than maximum mechanical strength.
Is Hastelloy C276 stronger than 316L stainless steel?
C276 can provide higher minimum tensile and yield strength than many 316L product specifications at room temperature, but strength is only one consideration. C276's major advantage is its broader corrosion resistance in severe chemical environments.
Does Hastelloy C276 lose strength at high temperatures?
Like most engineering alloys, C276 experiences declining strength as temperature increases. High-temperature design must consider temperature-dependent strength, creep, corrosion, and long-term microstructural stability.
Does Hastelloy C276 work harden?
Yes. Cold working and aggressive machining can increase surface hardness and strength. Appropriate machining practices are therefore important.
What is the density of Hastelloy C276?
The density is approximately 8.89 g/cm³.
What is the elastic modulus of Hastelloy C276?
The elastic modulus is approximately 205 GPa at room temperature.
What is the thermal expansion coefficient of Hastelloy C276?
Near room temperature, the coefficient of thermal expansion is approximately 11.2 × 10⁻⁶ m/m·°C, although the value changes with temperature.
Hastelloy C276 combines mechanical strength, ductility, toughness, and fabricability with the severe-environment corrosion resistance for which the alloy is best known.
The most important reference values for solution-annealed wrought material are approximately:
Mechanical Property | Reference Value |
Tensile strength | ≥ 690 MPa / 100 ksi |
Yield strength | ≥ 283 MPa / 41 ksi |
Elongation | ≥ 40% |
Density | ~8.89 g/cm³ |
Elastic modulus | ~205 GPa |
Poisson's ratio | ~0.307 |
Thermal expansion | ~11.2 × 10⁻⁶ m/m·°C |
Thermal conductivity | ~10.2 W/m·K |
The actual values should always be confirmed against the specific product form, heat-treatment condition, and applicable ASTM/ASME specification.
For C276, mechanical performance should also be considered together with corrosion resistance. The alloy's value lies not in maximum strength alone, but in its ability to maintain useful structural performance while exposed to demanding chemical environments.
For the complete material overview, visit the Ultimate Guide to Hastelloy C276.
