The melting point of copper is about 1084°C (1984°F).
Copper, chemical symbol Cu, is a naturally occurring metal with good ductility, good corrosion resistance, good thermal conductivity and good electrical conductivity. Copper’s main application markets include wires, pipes, manufacturing industries such as machining, and powder metallurgy.
In this blog, I’ll clearly explain the melting points of pure copper and copper alloys, what factors affect these melting points, and why understanding them matters.
Melting Point of Pure Copper
Pure copper, a purple-red metal, refers to those with a copper content of at least 99.3%. The melting point of pure copper is 1084.62 °C (1984.32 °F/1357.77 K).
Melting Point of Copper Alloy
The melting temperature of copper alloys vary significantly based on their compositions, so you need to consider both the alloy composition and melting point when selecting materials. Let’s take a look at the melting temperatures of common copper alloys.
Brass Melt Temperature
Brass is an alloy of copper and zinc, with a melting point of 900 to 1060°C (1650 to 1950°F). The exact temperature depends on the copper and zinc content, which is generally 60% to over 80% copper and less than 10% to 40% zinc.
Bronze Melt Point
Bronze is an alloy composed primarily of copper and tin, typically 88% copper and 12% tin. Bronze melts at approximately 913°C (1675°F), the exact value depending on the amount of copper, tin, and other elements (such as aluminum, manganese, or nickel).
Manufacturers use bronze to make many mechanical parts, including gears, clutch plates, bushings, bearings, etc.
Aluminum Bronze Melting Point
Aluminum bronze is an alloy consisting of 85%-95% copper, approximately 5% nickel and iron, and 12% aluminum. The melting point of aluminum bronze is between 1027°C and 1038°C (1881°F to 1900°F).
Tungsten Copper Alloy Melting Point
The melting point of copper tungsten alloy depends on the content of copper and tungsten, which is about 1084 to 2610°C. The higher the tungsten content, the higher the melting point. These alloys have good high temperature resistance, thermal and electrical conductivity and low expansion.
Beryllium Copper Melting Point
Beryllium copper, also known as beryllium bronze, is a copper alloy with 0.5 to 3% beryllium. Beryllium copper has a melting point of about 866°C (1590°F). It has good ductility, machinability and weldability.
Melting Point of Cupronickel
Cupronickel is an alloy of copper with nickel, the copper content is usually between 60% and 90%.
The melting point of cupronickel (copper nickel) is depending on the specific alloy composition.
- 90/10 Cupronickel (90% Copper, 10% Nickel): 1100–1150°C (2012–2102°F)
- 70/30 Cupronickel (70% Copper, 30% Nickel):1170–1240°C (2138–2264°F)
Due to its excellent high-temperature and corrosion resistance, cupronickel is commonly used in heat exhaust pipes and brine heaters for desalination plants, as well as in heat-transfer components for nuclear and fossil fuel power stations.
What Factors Affect the Copper Melt Temperature?
Some factors below affect the melting point of copper.
Alloying Elements
Alloying elements or impurities in copper metal will change the melting point. For example, nickel and tungsten will increase the melting point of copper, while lead or aluminum will reduce the melting point of copper alloys.
Atmospheric Pressure
Atmospheric pressure also has a slight effect on the melting point of copper. High atmospheric pressure may increase the melting point of copper, while low atmospheric pressure in the mountains may reduce its melting point.
Microstructure
The microstructure of copper also affects its melting temperature.
When the grain size of copper is reduced to the nanometer level, its melting point will be much lower.
Grain boundaries are the interfaces between grains, where atoms are arranged in disorder and have higher energy. The higher the proportion of grain boundaries (i.e., the finer the grains), the lower the energy required for melting, resulting in a lower melting point.
Environmental Factors
The surface of copper is oxidized to form copper oxide, which has a higher melting point of more than 1084 °C. When copper is exposed to reactive gases such as sulfur, impurities are introduced that lower the melting point.
Understanding the Significance of Copper Melting Point
It’s important to know the melting point of copper and copper alloys for practical and industrial applications
Industrial Processing:
It provides important information for casting, welding, brazing, and heat treating. Manufacturers must precisely control temperature to ensure that copper properties are not degraded when processed.
Material Selection:
Engineers use the melting point of copper to determine its suitability for high-temperature applications such as wires, heat exchangers, and other thermal management systems.
Thermal Stability:
Knowing melting points ensures your components will operate reliably within the specified temperature range without compromising mechanical strength.
How to Melt Copper?
Here are some ways to melt copper metal.
Induction Heating
Induction heating uses electromagnetic induction to heat copper quickly and efficiently.
It is common in industries that require precise temperature control, such as foundries and powder metallurgy powder production.
Gas Furnace Melting
You can also melt copper in a gas furnace, which is low-cost and suitable for large-scale melting operations.
Resistance Furnaces
Manufacturers also use electric heating elements to gradually melt copper, which features controlled temperatures and consistent melting.
Crucible Furnace Melting
Crucible melting is also a common method. In this process, you place the copper in a refractory crucible that is heated by fuel or electricity.
Arc Melting
In arc melting, manufacturers use a high-energy arc to melt the copper, usually under an inert gas shield to prevent contamination.
FAQ
What is the Melting Point of Copper Oxide?
Copper oxide exists primarily in two forms: copper(I) oxide (Cu₂O) and copper(II) oxide (CuO).
- Copper(I) oxide (Cu₂O) has a melting point of about 1232°C (2250°F).
- Copper(II) oxide (CuO) melts at a higher temperature, around 1326°C (2419°F).
