Hastelloy C-22HS
About Hastelloy C-22HS
Name and Equivalent Name: Hastelloy C-22HS, or UNS N07022 or Alloy C-22HS, complies with ASTM B575, B619, and B622. It is recognized under AMS 5885 and NACE MR0175 standards for corrosion resistance in critical industries. Known for its high strength and superior thermal stability, Hastelloy C-22HS is used in highly aggressive chemical environments.
Hastelloy C-22HS Basic Introduction
Hastelloy C-22HS is a high-strength variant of the C-22 alloy, combining excellent corrosion resistance with enhanced mechanical properties. It is designed to withstand severe oxidizing and reducing conditions, making it ideal for chemical reactors, gas scrubbers, and heat exchangers.
The alloy exhibits superior resistance to pitting, crevice corrosion, and stress corrosion cracking. Its ability to perform under cyclic fatigue and maintain strength at temperatures up to 850°C ensures durability in demanding environments. Hastelloy C-22HS also excels under long-term stress conditions, delivering reliable performance over extended service periods.
Alternative Superalloys of Hastelloy C-22HS
Hastelloy C-22HS can be substituted by other high-performance alloys based on specific needs. Hastelloy C-276 offers better resistance in strongly oxidizing environments, while Inconel 718 provides superior mechanical strength at higher temperatures. Alloy 20 is a better choice for sulfuric acid environments, and Monel K500 offers excellent corrosion resistance in marine applications. These alternatives serve different industrial requirements based on corrosion resistance and mechanical demands.
Hastelloy C-22HS Design Intention
Hastelloy C-22HS was developed to enhance both mechanical and corrosion-resistant properties. It is designed to maintain strength under extreme thermal conditions, withstanding temperatures up to 850°C. The alloy resists pitting, crevice corrosion, and stress corrosion cracking in oxidizing and reducing chemical environments.
The goal of the C-22HS variant is to provide long-term performance with minimal maintenance. Its enhanced fatigue resistance makes it suitable for components exposed to cyclic loads. The design ensures that the alloy performs consistently under prolonged thermal and mechanical stress exposure.
Hastelloy C-22HS Chemical Composition
The chemical composition of Hastelloy C-22HS optimizes corrosion resistance and mechanical performance. Molybdenum ensures resistance to pitting, while chromium provides oxidation resistance. Tungsten enhances the alloy’s strength at high temperatures.
Element | Content (wt%) |
|---|---|
Nickel (Ni) | Balance |
Chromium (Cr) | 20.0 - 22.5 |
Molybdenum (Mo) | 12.5 - 14.5 |
Iron (Fe) | 2.0 - 6.0 |
Tungsten (W) | 2.5 - 3.5 |
Carbon (C) | Max 0.01 |
Silicon (Si) | Max 0.08 |
Hastelloy C-22HS Physical Properties
Hastelloy C-22HS offers high density and thermal stability, providing excellent conductivity and mechanical strength in corrosive environments.
Property | Value |
|---|---|
Density (g/cm³) | 8.69 |
Melting Point (°C) | 1355 |
Thermal Conductivity (W/(m·K)) | 9.3 |
Modulus of Elasticity (GPa) | 206 |
Metallographic Structure of Hastelloy C-22HS Superalloy
Hastelloy C-22HS exhibits a face-centered cubic (FCC) structure, which improves its mechanical strength and corrosion resistance. This microstructure ensures uniform performance, minimizing the risk of phase separation and intergranular corrosion, even at elevated temperatures.
The alloy's metallurgical stability allows it to maintain ductility under thermal cycling and resist cracking. Its chemical composition prevents carbide precipitation, ensuring weldability and reliable performance during prolonged exposure to harsh chemical environments.
Hastelloy C-22HS Mechanical Properties
Hastelloy C-22HS demonstrates excellent mechanical strength, fatigue, and long-term stress resistance, ensuring superior performance in aggressive environments.
Mechanical Property | Value |
|---|---|
Tensile Strength (MPa) | 825 - 900 |
Yield Strength (MPa) | 500 - 700 |
Creep Strength | Excellent at 850°C |
Fracture Toughness | High |
Fatigue Strength | Good for cyclic fatigue conditions |
Creep Rupture Life | >10,000 hours at 850°C |
Hardness (HRC) | Rockwell C25 - 35 |
Elongation (%) | ~50 |
Elastic Modulus (GPa) | ~210 |
Key Features of Hastelloy C-22HS Superalloy
1. Superior Corrosion Resistance
Hastelloy C-22HS offers excellent resistance to oxidizing and reducing agents, making it ideal for chemical processing industries. It minimizes pitting, crevice corrosion, and stress corrosion cracking in aggressive environments.
2. High-Temperature Performance
The alloy maintains mechanical stability and strength at temperatures up to 850°C. This makes it suitable for applications requiring both thermal resistance and long-term durability.
3. Fatigue and Stress Resistance
Hastelloy C-22HS excels under cyclic fatigue conditions, making it ideal for components subjected to repeated thermal or mechanical stress, such as reactors and heat exchangers.
4. Weldability and Structural Integrity
With minimal carbide precipitation, Hastelloy C-22HS ensures reliable welds and prevents intergranular corrosion, making it suitable for industrial applications requiring extensive welding.
5. Extended Service Life
The alloy's high creep rupture life (>10,000 hours at 850°C) ensures reliable long-term performance, reducing maintenance and downtime in critical operations.
Hastelloy C-22HS Superalloy’s Machinability
Vacuum Investment Casting: Hastelloy C-22HS is not suitable for Vacuum Investment Casting due to its high molybdenum content, which limits fluidity and increases cracking risks during solidification. Alloys with higher castability are preferred for precise applications.
Single Crystal Casting: Hastelloy C-22HS is not used in Single Crystal Casting because its properties do not support single-crystal growth, an essential requirement for turbine blades and components under extreme mechanical stress.
Equiaxed Crystal Casting: While Hastelloy C-22HS can be used in Equiaxed Crystal Casting, it is not ideal for applications that require high mechanical strength over long durations at high temperatures.
Directional Casting: Hastelloy C-22HS is not recommended for Superalloy Directional Casting because it lacks the specific creep and thermal fatigue resistance needed for directionally solidified components.
Powder Metallurgy Turbine Disc: Hastelloy C-22HS is rarely applied in Powder Metallurgy Turbine Disc production, as turbine discs demand alloys optimized for mechanical endurance rather than chemical resistance.
Precision Forging: Hastelloy C-22HS is suitable for Superalloy Precision Forging, producing solid and corrosion-resistant components for critical chemical and energy industries.
Superalloy 3D Printing: Superalloy 3D Printing is feasible with Hastelloy C-22HS, offering flexibility for complex, corrosion-resistant designs used in chemical reactors and heat exchangers.
CNC Machining: CNC Machining with Hastelloy C-22HS requires specialized tools due to its work-hardening nature, ensuring precision and durability in industrial components.
Superalloy Welding: Superalloy Welding with Hastelloy C-22HS is practical, given its low carbon content, which minimizes carbide precipitation, ensuring robust and reliable joints.
Hot Isostatic Pressing (HIP): Hot Isostatic Pressing (HIP) enhances the performance of Hastelloy C-22HS by eliminating porosity and improving structural integrity for high-stress applications.
Hastelloy C-22HS Superalloy Applications
Aerospace and Aviation: Hastelloy C-22HS is utilized in Aerospace and Aviation for gas scrubbers, exhaust systems, and chemical handling equipment exposed to corrosive chemicals and high temperatures.
Power Generation: In Power Generation, the alloy is used for heat exchangers and gas scrubbers that operate under aggressive chemical environments, ensuring reliability and efficiency.
Oil and Gas: Hastelloy C-22HS is essential in Oil and Gas applications, such as pipelines and valves exposed to hydrogen sulfide, providing excellent resistance to chemical attack.
Energy: The alloy plays a key role in Energy systems, including chemical reactors and storage tanks, ensuring performance in high-temperature, corrosive environments.
Marine: In Marine environments, Hastelloy C-22HS is used for desalination systems and chemical handling equipment, ensuring resistance to saltwater corrosion.
Mining: Hastelloy C-22HS finds applications in Mining for chemical extraction systems, where it offers resistance to aggressive chemicals and harsh conditions.
Automotive: In Automotive applications, the alloy is used in exhaust systems and components for electric vehicles exposed to chemical environments.
Chemical Processing: Hastelloy C-22HS is widely used in Chemical Processing for reactors and heat exchangers, ensuring stability under highly corrosive conditions.
Pharmaceutical and Food: The alloy supports the Pharmaceutical and Food industries by ensuring equipment safety and withstanding aggressive cleaning agents while maintaining hygiene standards.
Military and Defense: Hastelloy C-22HS is utilized in Military and Defense for chemical storage systems and equipment, offering durability and corrosion resistance in extreme conditions.
Nuclear: The alloy is employed in Nuclear reactors and cooling systems, providing long-term corrosion resistance under high temperatures and pressure.
When to Choose Hastelloy C-22HS Superalloy
Custom superalloy parts from Hastelloy C-22HS are ideal for chemical resistance and mechanical strength environments. This alloy is designed for long-term use in highly corrosive conditions, including chemical reactors, gas scrubbers, and heat exchangers.
Hastelloy C-22HS performs exceptionally well under cyclic fatigue and high stress, ensuring durability in power generation, aerospace, and energy industries. It is particularly suitable for systems experiencing thermal cycling, thanks to its stability at temperatures up to 850°C. Hastelloy C-22HS provides reliability with minimal maintenance, reducing downtime and operational costs, whether for chemical storage or reactor components. Choose this alloy when performance and corrosion resistance are critical for your operations.
Explore Related Blogs
