Here's a breakdown of the typical composition ranges:
* Cobalt (Co): 30-65%
* Chromium (Cr): 15-35%
* Tungsten (W): 0-30%
* Molybdenum (Mo): 0-15%
* Carbon (C): 0.5-2.0%
* Other Elements: Small amounts of nickel (Ni), iron (Fe), silicon (Si), manganese (Mn), and sometimes boron (B) for improved properties.
Key Characteristics:
* High Hardness and Wear Resistance: The presence of cobalt and chromium contributes to its excellent hardness and wear resistance.
* Corrosion Resistance: Stellite alloys are highly resistant to corrosion, particularly in aggressive environments.
* High-Temperature Strength: The addition of tungsten and molybdenum enhances strength at high temperatures.
* Heat Resistance: These alloys have excellent heat resistance, making them suitable for use in high-temperature applications.
Specific Types of Stellite:
* Stellite 6: A commonly used alloy, it contains approximately 55% cobalt, 25% chromium, 15% tungsten, and 4% carbon.
* Stellite 21: A high-temperature alloy, it has a higher content of tungsten and molybdenum, typically around 30% and 10% respectively.
Applications:
Stellite alloys are used in various applications where high wear resistance, corrosion resistance, and high-temperature strength are required:
* Cutting Tools: Used in cutting tools like drill bits, milling cutters, and saw blades.
* Valve Seats: Used in valves for pumps, engines, and other machinery.
* Bearings: Used in high-load bearings for engines and other equipment.
* Dies and Molds: Used in dies and molds for forming metals and plastics.
* Aerospace Applications: Used in jet engine components and other aerospace parts.
In summary, Stellite is a versatile family of superalloys, each tailored for specific applications by adjusting the composition of cobalt, chromium, and other alloying elements.
