Copper Molybdenum Alloy
AOTCO has developed expertise in a wide variety of different elements, alloys, and metal mixtures for use in metal finishing. We love working with new and useful compounds, and if you do not see something on our materials list, please contact us. We enjoy the challenge of working with new things and broadening our catalogue.
What is Cu-Mo-Cu?
The metal finishing industry rarely has “one size fits all” solutions. Oftentimes it takes a team of platers, chemists, and engineers to find different combinations of metals and/or other materials that provide physical or chemical properties that are deemed desirable by our customers. One of those compounds is called Cu-Mo-Cu , also known as Copper Molybdenum Alloy or Copper Moly for short.
You may have noticed Copper-Molybdenum-Copper on our materials page. Cu-Mo-Cu is a metal composite comprising of a middle (core) layer of Molybdenum and two outer (clad) layers of copper. The compound is made through a process called roll-bonding, which layers levels of molybdenum and copper in top of each other like a sandwich.
Once stacked, it tightly bonds the interchanging levels of copper and molybdenum until the desired thickness ratio is acquired. The thickness ratio is determined by what kind of thermal coefficient is desired from our customers. The outcome is an incredibly unique and useful metal alloy that has the physical and chemical properties of both molybdenum and copper.
Cu-Mo-Cu | Copper Moly
These laminates have an adjustable coefficient of thermal expansion that can be correlated with a range of semiconductor substrates and still maintain high thermal conductivity. In short, they make an excellent heat sink. Anything that produces significant heat can benefit from using a Cu-Mo-Cu heat spreader. It takes highly localized heat sources and spreads the energy out through the layers.
If temperatures rise past the melting point of copper (1982°F), then the copper can liquify and act as a cooling agent for the molybdenum core. This is a great quality to possess when plating electronics and electrical components, as it prevents overheating during the transfer of electrical signals.
Due to their roll-bonding process, Cu-Mo-Cu laminates are tightly bonded. These tight bonds help increase the thermal resistance of the composites and the components they are protecting. These laminates can repeatedly reach levels of up to 1560°F (850°C) without consequence, making them an ideal pairing for microwave components or other parts that may be subject to constant and/or extreme temperatures.
Since the two metals have opposite thermal expansion coefficients (Copper has a High thermal expansion coefficient, Molybdenum low), this allows us to alter the coefficient of the alloy so that it matches the thermal coefficient of the other materials that it is being paired with. This prevents a great deal of stress damage that can occur when mismatching thermal coefficients.
When plating for any kind of electronics, it is important to match the thermal expansion with a given die. Thermal mismatch can create an incompatibility between the die and the heat spreader that should be avoided. Fortunately, the thermal expansion can be matched by varying the ratio of the molybdenum with the copper.
They are also subject to low electrical resistance, and in turn, high electrical conductance. This makes them suitable for silicon-based devices as well as area power devices. Copper provides a great deal of conductivity and low electrical resistance, and a very low coefficient of thermal expansion provided by the inner layer of molybdenum.
High Practicality and Machinability
In its purest form, Molybdenum has a high hardness level and is very brittle. These physical properties make it difficult to machine. Copper on the other hand, is much more malleable. The combination of the two causes the flexibility of the alloy to increase greatly, making it useful for machining or other parts that are subject to heavy use and/or wear.
Finally, Cu-Mo-Cu laminates are non-magnetic. This makes these parts incredibly useful when working with products that may contain small magnetic components that would otherwise be affected by a magnetic charge. The lack of magnetism makes these Copper Molybdenum composites a common pairing in a variety of intricate electronics.
Principal Uses of Cu-Mo-Cu | Copper Moly
Since CMC is a fantastic conductor of thermal energy it is often used in many aerospace components that experience frequent high temperature conditions. Some of these parts include nozzle shrouds, combustion chambers, and vacuum contacts. Many of these components may be found within jet engines and turbines.
Molybdenum Copper alloys are also often used in the defense industry. While it is most frequently used in missile components that experience high temperatures, it can also be utilized in range extenders for a variety of different weapons.
Due to the biocompatible properties of Cu-Mo-Cu it is often utilized in a variety of different medical tools and devices like surgical instruments or dental implants. Since the composite is also non-magnetic and highly conductive it is also used in a variety of medical electronics as well.
These are some principal uses of copper molybdenum alloys. As time goes on, this highly useful material continues to gain popularity in the metal finishing industry.
At AOTCO, we provide several metal finishing services to help you match the thermal expansion of your electronics. Whether that is the Cu-Mo-Cu, or another that we have covered in our blogs or listed in our materials page, we adhere to a high degree of quality and technical experience. Let us know how we can help you with your next metal finishing project. Contact us at 888-275-0880 or 978-667-8298 for more information.