Copper is a chemical element that is also a metal. Its key properties are that it has excellent electrical conductivity, high thermal conductivity, and good corrosion resistance. It is also ductile and has an interesting reddish-brown color. The combination of these properties leads to the wide application of copper for engineering and aesthetic uses.
What Is Copper?
Copper is a chemical element, number 29 on the periodic table of elements. The copper element symbol is Cu, from the Latin “Cuprum”. It is a ductile metal with a reddish-brown color. It is applied widely due to its high thermal and electrical conductivity.
What Is the History of Copper?
The history of copper dates back to 8,700 BC. A copper pendant that was discovered in Northern Iraq has been dated back to approximately that date and is currently thought to be the oldest object made of copper. Copper has been a crucial metal in many ancient civilizations, but it is generally agreed that the Mesopotamians (in Northern Iraq) discovered copper. In fact, a period in prehistory is the copper age between 5,500 BC and 4,000 BC, usually called the Chalcolithic Age from the Greek words for copper (chalkos) and rock (lithos).
Copper is one of few metals that can occur naturally in its native metallic form. This is different from most metals that need to be extracted via metallurgy from an ore. In places where native copper occurs, the technology of metallurgy was not necessary for those civilizations to begin to work with copper to form weapons and ornaments.
What Is the Other Term for Copper?
The other term for copper is the Latin word cuprum, which gives copper its symbol Cu on the periodic table of elements. The Latin name for copper was originally from the island of Cyprus, as the island was the major source of copper in ancient times. Cuprum was the “Metal of Cyprus.”
What Is Copper Made Of?
Copper is a chemical element. It is made of only a single type of atom – it cannot be broken down into simpler substances. The copper atom has an atomic number of 29, which means that its atomic nucleus contains 29 protons.
Copper is extracted from natural ores – either a copper sulfide ore (such as chalcopyrite) or a copper oxide ore. These ores are mined, crushed, and processed to make copper. These copper ores are found in parts of North and South America (countries such as Chile and Peru), as well as in areas such as the Ural Mountains in Russia, and in Zambia and the Democratic Republic of Congo in Africa.
What Are the Different Processes To Make Copper?
The different processes to make copper are described below:
1. Mining
Mining of copper ores is usually done in large open pit mines. These are open, stepped holes in the ground that are gradually dug deeper. Explosives are used to blast the rock, and the resulting boulders are transported for crushing into smaller pieces for processing.
2. Extraction
According to the two common types of copper ore, there are two main purification processes. A hydrometallurgical process is used for oxide ores. The crushed ore is heaped and an acid-leaching solution is percolated through the heap. This creates a pregnant leach solution. A pyrometallurgical process is used for sulfide ores. The extraction of the ore is done by froth flotation and thickening according to the density of the particles.
3. Purification
For oxide ores, hydrometallurgy is used. This means that the pregnant leach solution is sent to a solvent extraction process to concentrate the copper in the solution. This solution is then sent to electrowinning, where electricity is used to deposit the solid copper. For sulfide ores, pyrometallurgy is used, which means that a smelter is used to create the raw copper. This is then purified further by electrorefining.
4. Alloying
Copper alloys are manufactured by first melting the alloying material, and then melting the copper to add to it. The molten mixture is then cast and allowed to cool and solidify.
5. Electro-refining
Electrorefining of copper involves electrolytically dissolving impure copper material into solution. Pure copper is electrochemically deposited on an electrode by applying an electrical current through the solution. This removes impurities from the copper to achieve higher purity. However, the process is expensive and has a very high electrical demand.
What Are the Characteristics of Copper?
Copper metal has the primary characteristics of being an excellent electrical and thermal conductor. It is also malleable and ductile, which means it can be bent relatively easily. This makes it easy to work with, for example, with cabling being flexible. Another key characteristic of copper metal is its corrosion resistance, particularly in water and seawater environments. Finally, copper has the advantage of being aesthetically appealing, as it has a reddish-brown color and can be polished.
What Is the Color of Copper?
Copper is typically a reddish-brown color. However, pure copper before oxidation is actually a pink color, but the formation of brown copper oxide happens so rapidly that any readily available copper will be the common reddish-brown. Copper can also have a green tarnish (such as on the Statue of Liberty) – this is a copper carbonate.
What Does Copper Look Like?
Copper looks like a reddish-brown shiny metal. Copper can be processed into many different practical forms.
What Are the Different Types of Copper?
Copper is available in different types for different applications. The properties and applications of each grade of copper depends on the purity of the copper and what alloying elements (if any) are included. Listed below are the different types of copper:
1. Copper Wire
Copper wire takes advantage of the metal’s excellent electrical conductivity. It is the most common conductor for most electrical applications. It is used for large currents in industry, and also for domestic use, right down to the wiring within your home for outlets and lights.
2. Copper Tubing
Copper tubing has been widely used for domestic drinking water systems due to its corrosion resistance and therefore its longevity. Over the past few decades, it has been the standard in most of the world to use copper tubing for household plumbing. The tubes are available in different diameters and gauges (wall thicknesses). The high cost of copper and the emergence of improved plastic tubing materials means copper is becoming less frequently selected.
3. Copper Alloys
The two most common copper alloys are brass (alloyed with zinc) and bronze (alloyed with tin). Brass is typically applied more widely. It is used for plumbing fixtures, musical instruments, and decorative items. The addition of zinc gives the alloy a higher strength and ductility. Bronze has very similar characteristics to copper, such as: its high thermal conductivity, excellent ductility, and resistance to saltwater corrosion. Bronze is therefore used for bearings and bushings, as well as ship impellers.
4. Pure Coppers
Pure copper is specifically prepared to ensure a minimum of impurities, maximizing the thermal and electrical properties of copper. Pure copper tends to be softer and less tough than copper with additives or minor alloying materials. It is ideally used in precision electrical components, for which its electrical conductivity and low thermal expansion are ideal.
5. Copper Nanoparticles
Copper nanoparticles are very small particles of copper, or copper-based materials, that are within the size range of 1–100 nm. Nanoparticles have been found to have behaviors different from those of bulk materials. In the case of copper nanoparticles, they show very high catalytic activity for industrial chemical reactions, likely due to their large surface-area-to-volume ratio. Further, copper nanoparticles have shown excellent antimicrobial effects.
6. Free-Machining Coppers
Free-machining coppers have minor amounts (<1%) of other alloying elements added to improve the machinability of the copper. Free-machining copper can then be more easily machined into items such as welding nozzles and soldering iron tips.
7. Copper Sheets and Plates
Copper sheets are thin sheets of copper (about 2 mm or less), while plates are thicker (up to 12 mm thick). Generally, these are available in different copper grades. The sheets are highly malleable and can be formed into different components.
8. Oxygen-Free Coppers
Oxygen-free coppers are melted under a granulated graphite bath to exclude oxygen. They are the purest coppers available, with minimal impurities due to the non-oxidizing conditions. Its high electrical conductivity and low volatile impurities make it suitable for use in high-vacuum electronics.
9. Electrolytic Coppers
Electrolytic coppers are refined by electrolysis within a solution to remove impurities. This high-purity grade of copper has high electrical conductivity and therefore is employed in various electrical components such as bus bars and windings.
What Are the Applications of Copper?
The applications of copper are found throughout everyday society. Listed below are some common examples:
1. Electronics
Copper is used widely in electronics as it has excellent electrical conductivity. It allows currents to be carried on smaller cross-sections of copper compared to aluminum, allowing less bulk to be used, and components to be smaller.
2. Architecture
Copper is used in architecture for an aesthetically striking appearance. It has been used for roofing and wall cladding, as well as gutters and rainwater downspouts.
3. Plumbing
Copper tubing is used widely for domestic water piping in households, due to its very good corrosion resistance.
4. Transportation
Copper is used extensively in modern vehicles due to the amount of electrical cabling used for complex electronics. As electric vehicles grow in market share, increasing amounts of copper are used for elements such as electric motors. This is due to copper’s excellent electrical conductivity, second only to silver.
5. Renewable Energy
Copper is used within the renewable energy market in a number of ways. For instance, wind turbines use copper within the generating turbines. Solar photovoltaic panels also require copper for connections and cabling.
6. Medical Equipment
Copper is used as a coating on medical equipment due to its antibacterial properties. In this way, it reduces the risk of infection in patients.
7. Electrical Wiring
Copper is used widely for electrical wiring due to its excellent electrical conductivity. The cross-section of copper required to carry a particular current effectively is less than other reasonably available materials such as aluminum.
8. Coinage
Copper has historically been used in coins for a number of reasons: it is malleable and therefore easily stamped, but still durable enough to survive in circulation. It also has antimicrobial properties and corrosion resistance.
9. Industrial Machinery
Copper is used in a variety of ways in industrial equipment, with services such as copper die casting. Apart from electrical applications such as motors and cabling, it is also used in heat exchangers such as refrigeration condensers. It may also be applied for particular chemical resistance.
