Overview
When discussing 
Stellite alloys, Stellite 6 and Stellite 12 are two of the most commonly used alloys that cannot be ignored. When choosing a material, you will inevitably have questions. What are the differences between these two alloys? Which alloy should I choose to meet my needs?
In this article, we will compare these two corrosion-resistant and wear-resistant cobalt-based superalloys in detail by analyzing their chemical composition.
Basic Information
Name
Stellite 6
UNS R30006
Brand
SATELLITE®
Matrix
Density
8.44 g/cm³
Use Temperature
High Temperature
Name
Stellite 12
UNS R30012
Brand
SATELLITE®
Matrix
Density
8.5 g/cm³
Use Temperature
High Temperature
Introduction
Stellite 6
Stellite 6 is the most widely used of the wear resistant cobalt-based alloys and exhibits good all-round performance. It is regarded as the industry standard for general-purpose wear resistance applications, has excellent resistance to many forms of mechanical and chemical degradation over a wide temperature range, and retains a reasonable level of hardness up to 500°C (930°F). It also has good resistance to impact and cavitation erosion.
Stellite 12
Stellite 12 is a cobalt-base alloy having high heat and corrosion resistance with excellent wear and abrasion resistance. Examples include industrial knives for cutting carpets, plastics, paper and synthetic fibers; and saw tips in the timber industry. It is also used for control plates in the beverage industry, pump vanes, bearing bushes and narrow neck glass mold plungers; and for hardfacing of engine valves, pinch rollers in the metal-processing industries and rotor blade edges.
Chemical Composition
Corrosion Resistance
Stellite 6
lose
Stellite 12
WIN
Corrosion resistance is a key characteristic of Stellite alloys. As a cobalt-chromium-tungsten alloy, chromium is the crucial element determining its corrosion resistance. Upon contact with oxygen, it forms a dense chromium oxide film on the alloy surface, preventing further oxidation.
In comparison, Stellite 12 has a significantly higher chromium content than Stellite 6. As a result, Stellite 12 exhibits better corrosion resistance than Stellite 6. Therefore, you can decide which material to use based on the corrosion resistance requirements of your project.
High Temperature Resistance
Stellite 6
WIN
Stellite 12
lose
In cobalt-based alloys, cobalt is the element that determines the alloy's high-temperature resistance. As the alloy's matrix, cobalt not only gives the alloy a higher melting point but also improves its resistance to hot corrosion. Therefore, Stellite 6, with its higher cobalt content, exhibits relatively higher high-temperature resistance.
Wear Resistance
Stellite 6
lose
Stellite 12
WIN
Wear resistance is the core property of Stellite alloys. Carbon and tungsten are the determining factors for wear resistance. Stellite 12 alloy has significantly higher levels of both carbon and tungsten than Stellite 6. Therefore, Stellite 12 has a comprehensive advantage in wear resistance. In fact, among all Stellite alloys, Stellite 12 ranks among the top in terms of wear resistance.
Main Standards
Stellite 6
Filler Metal: AWS A5.21 ERCoCr-A
Welding Electrode: AWS A5.13 ECoCr-A
Stellite 21
Filler Metal: AWS A5.21 ERCoCr-B
Welding Electrode: AWS A5.13 ECoCr-B
Price
Stellite 6
Tie
Stellite 12
Tie
You might assume that Stellite 12, with its superior corrosion resistance and wear resistance, would be more expensive. While that's not entirely wrong, the actual price difference between the two materials is not significant. On one hand, Stellite 6 has a higher cobalt content, which effectively eliminates the price difference. On the other hand, Stellite 12 has a higher tungsten content, which increases the price of Stellite 12 despite its lower cobalt content.
Conclusion
Stellite 6 and Stellite 12 are both high-performance wear-resistant alloys. Due to its higher chromium, tungsten, and carbon content, Stellite 12 exhibits superior corrosion and wear resistance. Conversely, Stellite 6, with its higher cobalt content, excels in high-temperature performance.
We manufacture Stellite 6 and Stellite 12 strictly according to standards. If you have any purchasing needs, please contact us via the email address below:
