What Is Copper? Everything You Need To Know

Copper is among the few elements that are found on Earth in usable form. It is an excellent conductor of electricity and is widely used in day-to-day applications. Among its various types, some are used in Computer Numerical Control (CNC) machining. Here, I will explain everything about copper, its properties, usage, price, grade, and more.

What is Copper?

Copper is the 29th element of the periodic table. It is a reddish-brown element that is popularly used in CNC machining. Copper has impeccable electrical and thermal conductivity, is highly corrosion resistant, and has excellent ductility and malleability. 

This is one of the most used metals with anti-microbial properties, and it has wear and tear resistance. Copper comes in both metal and alloy forms, and its different properties make it appropriate for versatile uses.

Reactivity of Copper

Copper does not react easily with water and non-oxidizing acids. When it comes in contact with moist air, copper forms a green layer (copper carbonate) on itself to prevent itself from corrosion.

In terms of acids, in normal conditions, copper does not react with dilute hydrochloric and sulphuric acid. However, it does react with nitric acid and other oxidizing acids (forming copper nitrate and releasing nitrogen dioxide) and halogens (forming copper halides).

Properties of Copper

Physical Properties

Copper has a reddish-brown color with a metallic finish. It becomes green when exposed to humidity and moisture as it forms a copper carbonate layer on top to protect itself from corrosion. 
It has a density of approximately 8.96 g/cm3 and is highly malleable and ductile, which means it can be easily hammered into thin sheets and wires. Copper has a melting point of 1,085°C (1,984°F) and a boiling point of 2,562°C (4,644°F).

Mechanical Properties

Pure copper has a tensile strength of approximately 200MPa, which can be a problem while machining; hence, it needs to be clamped securely to prevent deformation. It has an elastic modulus of 110-128GPa and a yield strength of around MPa. 

Use sharp cutting tools to maintain precision if you are working with the pure form. It is soft with a Brinell hardness ~ HB 35, but it can be hardened by alloying.

Chemical Properties

Copper is a non-toxic element in solid form. It is non-corrosive in a dry environment and remains stable in water and non-oxidizing acids. It forms copper oxides (Cu₂O, CuO) when it comes in contact with oxygen at higher temperatures.

Electrical and Thermal Properties

Copper is the second-best conductor of electricity (the first is silver). It has a conductivity of 5.96X10⁷S/m and a thermal conductivity of 385W/m\cdotpK. It is non-magnetic and has a heat capacity of 0.385 J/g\cdotpK.

Types of Copper

Oxygen-Free Coppers

• Grade:  OFC (Oxygen-Free Copper), OFHC (Oxygen-Free High Conductivity Copper)
• Purity: 99.95% to 99.99%
• Applications: Medical equipment, aerospace, industrial usage, electronics, etc.

This is the purest form of copper with very little or no oxygen content. It provides maximum electrical and thermal conductivity and durability against various factors.

Electrolytic Copper

• Grade: ETP (Electrolytic Tough Pitch Copper)
• Purity:  99.90% to 99.95%
• Applications: Power cable, wiring, busbars, transformers, etc.

The electrolytic copper is very ductile, making it easy to work with. It can be used to form wires, sheets, and other components. ETP is also a pure copper and provides excellent conductivity.

Beryllium Copper (BeCu)

• Grade: Alloy 25 (C17200), Alloy 190, Alloy 17510
• Purity: Beryllium 0.5% to 3%
• Applications: Oil, gas, electronics, medical, defense, aerospace, etc.

Beryllium copper is perfect for use in hazardous environments. It is non-sparking, corrosion-resistant, and has excellent strength and conductivity. Satellite components, airplane gear, switches, surgical and medical equipment, etc., are made with this.

Deoxidized Coppers

• Grade: DHP (Deoxidized High Phosphorus Copper), DLP (Deoxidized Low Phosphorus Copper)
• Purity: 99.90%
• Applications: Heating systems, roofing, marine applications, architecture, plumbing, etc.

You can use deoxidized coppers in less demanding applications. It is more corrosion-resistant and performs well in salty environments. It does not have oxygen, making it less electrically conductive, but it has amazing thermal conductivity.

Commercially Pure Copper

• Grade:  C11000 (Electrolytic Tough Pitch), C12000 (Phosphorus-Deoxidized), C12200 (High Phosphorus)
• Purity: 99.90%
• Applications: Industrial usage, electrical components, construction, etc.

Commercially pure copper has a multi-purpose usage. It is more affordable than other types and provides general conductivity and malleability. It is appropriate for use where high purity is not an issue.

Specialty Pure Coppers

• Grade: Chromium Copper (C18200), Zirconium Copper (C15000), Cadmium Copper (C16200)
• Purity: 99%(+)
• Applications: resistance welding electrodes, heat exchangers,  switchgear components, trolley wires, commutators, etc.

The specialty pure coppers are alloyed with special elements, which enhances their quality and makes them suitable for special applications. These can endure more stress, are more stable, and can endure higher temperatures.

What Is Copper Used For? – Application

Copper is a versatile metal with numerous applications. Its malleability, durability, strength, and resistance make it perfect for different industries.

Electrical Applications

One of copper’s main properties is its high conductivity, which is used in various electrical applications. It can be used to make efficient power transmissions like wiring and cable.

Copper wires and cables are used in homes, offices, and even in commercial projects. Electromagnets made with copper are used in scientific and industrial equipment, as well as in Printed Circuit Boards (PCBs), which are used in smartphones, laptops, TVs, etc.

Thermal Applications

Another functional usage of copper is that it is a great thermal conductor. It transfers heat efficiently in various applications. Heat exchangers that you find in radiators, HVAC, and cooling systems are made with copper. Apart from that, copper is used in industrial boilers and cryogenic applications where stability is essential in extreme cold conditions. 

Vacuum and Cryogenics

Since copper is non-magnetic, its vacuum tightness properties enable it to be used in specialized applications like vacuum tubes. It ensures stability in cryogenic systems, and it is also found in high-end telescope components where precise imaging is necessary.

Industrial Equipment

Industrial equipment like pipes, manufacturing components, chemical processing machines, and tubes are made of copper for their amazing durability, malleability, and corrosion resistance properties. Components of air conditioners and refrigerators are also made with copper.

Marine and Aerospace

Components used in ships, airplanes, and even desalination plants, hulls are made with copper for their strength and resistance to saltwater. Copper is also used in seawater pipelines.

Precision Tooling

Copper, when alloyed with other metals, becomes more strong and durable. It is used in making molds and dies that are used in the production of metal and plastic parts. They are used to make resistance welding equipment and perform precision machining. 

Medical Devices

Another key factor of copper is its antimicrobial properties, and it is widely used in medical precision tools and equipment. It is a critical material in healthcare used in the manufacturing of X-ray and MRI machines. Copper is also used to make IV poles, bed rails, and door handles.

Military and Defense

Copper’s strength, reliability, non-corrosion, and non-sparking properties make it a useful element for military and defense applications. It is used for ammunition casting, has a reliable conductivity in signal transmission, and is also used to make submarine and naval vessels.

Automotive Industry

In modern automotive systems, copper plays a significant role. It is used to make Electric Vehicles (EVs) and wiring harnesses, and it is also found in motors and batteries. Copper is a key component in making radiators and heat exchangers as it ensures instant cooling. Furthermore, it is used to make brake components, sensors, and control units. 

Robotics Industry

Copper plays a significant role in the robotics industry as well. It is reliable and saves energy. The motor and actuator, wiring, and connector of robot joints and controllers are made from copper. Copper works excellently for heat management; hence, it is used in robotic hardware and sensors.

What is the Price of Copper?

The price of copper is $4.12 per troy ounce as of December 2024. Given that copper’s price varies for a number of reasons. Global economic health, disruptions in supply and demand, and technological advancement are a few examples. 

The surge in the use of electronic vehicles has increased the demand for copper in recent years, which is also a factor in the price hike.

However, the increasing copper price can be regulated if we can reduce our dependence on newly mined copper and focus on recycling copper. Other factors, like choosing a substitute for copper, can stabilize its demand over supply. For example, aluminum is used for radiators and power cables.

Natural Sources of Copper

Copper occurs naturally in various ways within the earth’s crust. It can be extracted from biological systems, minerals, and geological formations. Chalcopyrite (CuFeS₂), bornite (Cu₅FeS₄), malachite (Cu₂(CO₃)(OH)₂), and azurite (Cu₃(CO₃)₂(OH)₂) are among the most copper-bearing minerals found on earth. 

These minerals are located around volcanic areas and hydrothermal veins where significant geological activities take place. However, a small portion of copper can be found in Keweenaw Peninsula in Michigan, USA. 

Other significant sources of copper are Kupferschiefer deposits in Poland and Germany, as well as Volcanic massive sulfide (VMS) deposits. Some secondary sources of copper are the copper belts of Zambia and the Congo.

The Copper Extraction Process

Copper is not usable in raw form. There is a step-by-step extraction process to separate copper from unwanted materials.

Mining

Mining is digging up the rocks from underground tunnels. Since copper is found underground, large open pits are dug to extract rocks with copper.

Crushing and Grinding

To separate the copper from junk, the rocks that were mined are crushed in crushers and then ground in fine powder in machines to make the separation process more manageable.

Concentration

In a tank, the powder is mixed with water and chemicals in a process called flotation. This process makes the copper particles float to the surface. The concentrated copper ore is then collected, leaving the waste.

Smelting

The concentration process does not completely separate the copper from the waste. For that, the copper ore is heated in a furnace, separating the ore from the dirt. It creates blister copper, which is extracted and is approximately 99% pure (but not 100%). 

Electrolysis

Even after concentration and smelting, the copper is still not pure enough. The final step of electrolysis is to purify the copper and to make it usable. Electric current passes through the copper while placing it in a solution. This step effectively cleans impurities, leaving 99.99% pure copper. 

Copper Manufacturing Process 

After extracting pure copper through the extraction process, it is manufactured into various products that are used in different industries.

Step 1: Casting

After electrolysis, the basic shape of copper is given for further processing. The pure copper is melted and poured into molds to form large copper blocks called ingots or slabs.

Step 2: Forming and Fabrication

The copper blocks (ingots) then pass through machines to make them flexible and workable to make the desired products, e.g., wires, sheets, rods, etc.

Step 3: Alloying

To make other copper components stronger and more durable, copper is mixed with other elements, creating alloys, e.g., brass (copper + zinc), bronze (copper + tin), etc.

Step 4: Recycling of Copper

Copper can be recycled to make new copper products. Recycling old copper saves time and money and eliminates the need to mine new copper.

Advances in Copper Technology

With the advancements in technology around the globe, new, innovative uses of copper are surfacing every day along with advancements in copper technology. 

Efficient Copper Alloys

Copper alloys like beryllium copper and copper-nickel alloys are much stronger, more resistant, and have better conductivity.

These are used in places like aerospace technology and marine environments for their non-sparking properties and exceptional strength. Copper-nickel alloys are resistant to seawater corrosion. They are also used in renewable energy and thermal power plants.

Nanotechnology

Nanotechnology has been a huge milestone in copper advancement. It introduced nano-copper particles that are used in electronics and coatings. Nano-copper particles have better thermal and electrical conductivity and are being utilized in the latest printed circuit boards and 3D printing. 

Smelting and Refining Processes

Flash smelting and hydrometallurgical processes are two of the latest advancements in copper technology. These help reduce energy consumption and emissions, making the process environmentally friendly.

Energy-Efficient Electrical Applications

Solar panels, wind turbines, and EVs now use copper for efficiency and better power generation. It also enhances the performance of the equipment, making an immense impact in the field of renewable energy.

Antimicrobial Copper Surfaces

It has been recently discovered that copper surfaces have excellent antibacterial properties. It helps reduce the spread of infections, and it is now widely being used in healthcare facilities and public places.

Recyclable Copper Innovations

Thanks to advances in recycling technologies, copper is now 100% recyclable. Technologies like electrochemical refining help remove impurities from recycled copper and make it similar to newly mined copper.

Advantages and Disadvantages of Copper

Advantages of Copper

• Excellent electrical and thermal conductivity 
• Low maintenance 
• Durable 
• Easy to shape
• Antimicrobials are perfect for hospitals or places where hygiene is a concern. 
• Eco-friendly
• Non-sparking
• Corrosion-resistant
• Aesthetic appeal

Disadvantages of Copper

• It might be a bit heavier for some people.
• It is not resistant to moisture and air.

Conclusion

Copper is an amazing material with multi-purpose uses. At Richconn, we manufacture all kinds of CNC machining products and offer a wide range of metal options depending on your needs. 

Whatever your requirements are, our experts understand and tailor-make your orders in top-notch quality. Established in 2003, Richconn is delivering world-class metal machining services to esteemed clients. Contact us now, request a quote, or ask about our services.

FAQs

What are the primary uses of copper?

Copper is a versatile material that is used in various industries. It is used in industrial and construction use, renewable energy systems, electronics, solar panels, etc.

Why is copper essential in electronics?

Copper is essential in electronics because of its great ductility and thermal conductivity properties. It also has excellent thermal conductivity, making it perfect for thermal and electrical uses.

Why does copper turn green over time?

Copper, when it comes in contact with oxygen, water, and carbon dioxide in the air, it reacts and forms a layer of copper carbonate. This layer is green in color, and it is formed to protect the copper from further corrosion.

What is the atomic mass of copper?

The atomic mass of copper is 63.55 u (atomic mass units). This is an important parameter in chemistry that influences calculations involving molar masses and stoichiometry.

Where are the copper deposits around the world?

Major countries with natural sources of copper are Chile, with a global share of 23.2%; Peru, 12.0%; the United States, 5.1%; China, 7.9%; Australia, 3.8%; Zambia, 3.5%; Congo, 11.6%; Russia, 4.2%; Indonesia, 3.9%; and Mexico, 3.5%. Note that these statistics can change every year due to mining output, geopolitical events, and economic conditions.

What is the atomic number of copper?

The atomic number of copper is 29. The atomic number determines the position of an element in the periodic table. In the case of copper, it is located in group 11 and period 4.