Cobalt is used in a broad spectrum of areas ranging from health to lithium batteries to the aerospace industry. Cobalt alloys have found their place and utility in many industries. Each benefits, in their own way, from the many characteristics of this metal and the alloys of which it forms part.
It was initially for the needs of its automotive industry that Haynes developed Stellite. He discovers a corrosion resistant product and subsequently, its incredible resistance to wear, which will have the effect of extending the use of its product and ensure the success of its business.
Over time, the alloy has been given three major characteristics: high resistance to heat, wear and corrosion.
Today, there are twenty or so Cobalt-based alloys. All compounds to meet the needs of the industry and the sector for which they are intended. There is therefore no single chemical “recipe” in the combination of Cobalt alloys.
The first characteristic of Cobalt alloys is at the base of its initial use: its high resistance to corrosion. It is to chromium, the second “ingredient” of the alloy that we owe this particularity. According to several tests, the alloy responds positively to the exposure of several different acid substances.
Thus, Cobalt 6, especially used in seawater at a temperature of 20 degrees Celsius, would lose only 0.05 mm of surface per year. (Deloro stellite)
Cobalt-based alloys are also very resistant to wear.
The carbon that is contained in the alloy plays a major role in the hardness of the product. A larger amount of carbon increases the wear resistance, while a small portion of carbon will give a more heat resistant product. This addition of carbon in the alloy creates a layer that makes the alloy more resistant to wear.
This feature gives these alloys an interesting life.
Cobalt 6 parts used by some industries, especially oil, can last several months, compared to a few days for standard alloy steel parts and others.
Although several metals have a high melting point, Cobalt is well suited for long-term tests. Although Nickel alloys are often more popular, the melting point of Cobalt is more important, allowing it to remain stable longer under the stress of heat. Cobalt can maintain its integrity, strength and toughness even when it is “red hot”.
This advantage allows it to maintain its strength under significant heat and to avoid the corrosion and wear that some other premises undergo, making it a choice piece in some industries.
Stellite has often found itself in space rocket propulsion constructs due to this specificity. This alloy is also found in the composition of the guns of some machine guns which must maintain their precision throughout their use.
Cobalt-based alloys are also easily welded according to the selection of the right procedure.
Finally, although Cobalt is the base of each of these alloys, it has often been analyzed that the proportion of this metal in the alloy could be reduced up to 30% without losing the much sought after properties of this alloy.
For more information about the properties of cobalt parts vs your specific applications, please contact us by phone at (514) 236-5441 or by email at