55 HRC -60 HRC Cobalt Based Alloys Stellite 21 High Temperature Resistant

Stellite 21 Alloy Offers Excellent Wear, Corrosion, And High-Temperature Resistance.

Stellite 21 Alloy is a cobalt-based alloy designed for high-performance applications that require excellent wear resistance, hardness, and corrosion resistance. It is particularly effective in environments subject to high temperatures and abrasive conditions.

Detailed Product Description:

Stellite 21 Alloy is engineered to provide superior performance in severe service environments. It combines cobalt with chromium, tungsten, and carbon to create a material that excels in applications requiring resistance to wear, corrosion, and high temperatures.

Chemical Composition:

Stellite 21 Alloy has the following chemical composition:

• Cobalt (Co): 50-60% – Base metal providing high-temperature strength and corrosion resistance.
• Chromium (Cr): 28-32% – Enhances oxidation and corrosion resistance.
• Tungsten (W): 5-10% – Increases hardness and wear resistance.
• Carbon (C): 2.0-3.0% – Forms carbides that enhance hardness and strength.
• Nickel (Ni): ≤3% – Improves toughness and resistance to corrosion.
• Iron (Fe): ≤3% – Adjusts mechanical properties.
• Silicon (Si): ≤1% – Aids in deoxidation during production.

Mechanical Properties:

• Hardness: 55-60 HRC – Provides high wear resistance.
• Tensile Strength: Approximately 1,200 MPa – Ensures strength under mechanical stress.
• Density: 8.6 g/cm³ – Offers robustness in demanding applications.
• Ductility: Low – Suitable for applications requiring minimal deformation.
• High-Temperature Performance: Retains hardness and wear resistance up to 800°C.

Corrosion and Wear Resistance:

• Wear Resistance: Excellent resistance to both abrasive and adhesive wear, making it ideal for cutting tools and wear parts.
• Corrosion Resistance: High resistance to a wide range of corrosive environments, including acids, alkalis, and seawater.
• Oxidation Resistance: Maintains properties and structural integrity in high-temperature oxidizing environments up to 800°C.

Applications:

Stellite 21 Alloy is used in various demanding applications, including:

• Cutting Tools: Ideal for tools exposed to severe wear and high temperatures.
• Valve Seats and Stems: Suitable for industrial valves handling corrosive and abrasive fluids.
• Aerospace Components: Applied in parts exposed to extreme temperatures and mechanical stresses.
• Oil and Gas Industry: Used in downhole tools, valves, and other equipment in harsh environments.
• Industrial Machinery: Employed in machinery and components requiring long-lasting wear resistance.

Heat Treatment:

Stellite 21 Alloy can be heat treated to enhance its properties:

• Solution Annealing: Relieves internal stresses and improves corrosion resistance.
• Aging: Increases hardness and wear resistance by precipitating carbides.
• Hardening: Achieves optimal hardness and wear resistance through controlled cooling.

Summary:

Stellite 21 Alloy is a high-performance, cobalt-based material known for its exceptional wear and corrosion resistance. Its robust chemical composition and mechanical properties make it suitable for critical applications in cutting tools, aerospace, oil and gas, and industrial machinery. The alloy’s ability to maintain its properties at high temperatures ensures durability and reliability in demanding environments.