If you’ve ever stared at two pieces of metal like brass and copper for more than a minute without knowing the difference, then this article is for you. Despite their similarities, especially from visual inspection, their different properties make it easy for a trained eye to easily tell them apart. Even if you only appreciate their metallic attributes, you should be able to use properties like electrical and thermal conductivity, antirust, weight, and color to identify them. It might also come in handy in your selection of the most suitable material for your project. Notwithstanding, this article will give you all the information you need to distinguish between brass and copper even if you started reading this article as a metallurgical rookie. So, if you’re ready, let’s dive in.
I. Identifying Brass and Copper?
To the meat of the matter – the individual definition and identification of each metal. These two materials, brass, and copper have seen kingdoms rise and fall and yet they’ve remained relevant and versatile materials for different applications. Their usage spans several industries and uses all compliments of their unique properties.
A. What is Brass?
The uniqueness of brass depends on its primary constituents – zinc and copper, as these two materials significantly determine its properties with variations in amounts of each in the combination. In terms of physical properties, brass is known for its durability, antirust, hardness, and an easily recognizable golden-yellow color. However, the ratio of zinc to copper in this alloy can reduce or increase these properties. More zinc results in a harder and less-yielding brass material when subjected to stress. But zinc is never the only constituent of brass. Other materials, including aluminum, lead, and tin also contribute to the resulting properties of brass such as increased strength, antirust, and malleability. You’ll often find brass as a material of choice where specific requirements of strength, malleability, and durability are priorities. These applications include musical instrument materials such as guitar strings and plumbing fittings. It is also used for works of art and decorations.
B. What is Copper?
Next up is copper, a soft material praised in the electrical industry for its high electrical and thermal conductivity. It is often found naturally pure, which has accounted for its use for so many eons as it does not need any refining process that requires sophisticated technology and huge funds. Its softness makes it easy to shape into different forms and shapes. With a reddish-brown color, it shouldn’t be a problem to pick out copper among other similar-looking metals. However, its properties like anti-corrosion and durability which is common to that of brass make it suitable for plumbing fixtures and artistic applications. Nevertheless, its other properties like antimicrobial, electrical, and thermal conductivity make it suitable for electrical material manufacture, medical instruments, and marine components.
II. Brass and Copper: The difference
The difference between the two materials is especially noticeable when considering their properties and so, every individual should understand these properties to differentiate between brass and copper. Also, if you decide to use any of them for your project, you’ll definitely need these differentiating properties to arrive at a suitable material for your project. Here are the unique differences highlighted below.
- Element Composition: while brass combines two elements – copper and zinc, in different amounts to form an alloy, copper exists naturally as a single element with little to no impurities. For brass, to get a specific property like strength, the variation of the mix between copper and zinc will vary depending on the intended strength. Nevertheless, there are still some elements like aluminum, lead, and iron that can be added to increase other properties.
- Corrosion Resistance: The ability to resist corrosion is a shared property. Both copper and brass have this ability. However, brass has less of these anti- rust properties with copper coming out tops with more corrosion resistance and anti-tarnish properties. With brass, the presence of zin is the underlying reason for the less corrosion-resistant property as it gets oxidized quickly forming a layer of protection known as patina. This patina is also responsible for its dull looks.
- Electrical Conductivity: Brass again has less of this property though maintains a satisfactory conductive ability. Copper on the other hand is a highly conductive material making it a suitable choice for electrical material manufacturing, especially for wiring and cables.
- Thermal Conductivity: To absorb and dissipate heat into the environment is a requirement for things like heat sinks which often use copper as it has very high thermal conductive abilities. Brass is often used for low heat dissipating components like radiators because of its low thermal conductivity.
- Melting point: Sometimes you need materials that can withstand high heat without losing their material integrity for your projects. With a melting point of 1084°C, copper has a high melting point. However, you can vary the amount of zinc in brass to arrive at a relatively high melting point for brass by using less zing in the alloy, especially for mold manufacturing.
- Hardness: The ability to withstand forces and stress per unit area of material is often a required engineering property in design. The material with the highest resistance to stress and force is often brass as its zinc component ensures that it is very hard to avoid wear and tear. The more zinc, the harder the brass.
- Weight: Another important property is the unit weight of materials which often determines its suitability for stability and sometimes for areas that require less weight. With this property, copper with a density of 8.96 g/cm³ has more weight than brass and may be suitable for areas where rigidity is an important requirement. However, brass can vary in weight depending on the amount of zinc present in the alloy.
- Durability: For longevity and increased life span, durability is often a major requirement in engineering design and materials with wear and resistance like brass is often very suitable for this purpose. Brass presents better wear and tear resistance as the zinc composition ensures that it comes out strong. Hence, why it is used for such components as door keys, handles, and locks as these components are subjected to forces that can quickly deteriorate the quality of material if not strong.
Machinability: Sometimes you need to employ equipment like CNC machining in production and the ability to easily shape material using machines is quite important. thanks to the high malleability property of brass which makes it suitable in forming a variety of decorative shapes and forms.
- Formability: This property relies on the ductile nature of materials which ensures the material does not break while forces are applied to shape it. Copper carries the day for this property as it is more ductile than brass.
- Weldability: Using heat to join materials together is known as welding and many components in the manufacturing industry undergo this process to arrive at a finished product. However, copper outshines brass in this aspect as it is easier to weld than brass. One major reason for the low weldability of brass is its relatively low melting to that of copper.
- Yield Strength: The ability to withstand forces for a long time without noticeable deformations is a critical requirement for many components. This is why brass is often used for components that require this property, seeing that it has more yield strength than copper.
- Ultimate Tensile Strength: The tensile strength of the material allows it to support loads without any failure to its structural integrity due to bending. Brass again has more ultimate tensile strength than copper as it is able to support more loads than copper.
- Shear Strength: The ability to support loads without breaking is yet another engineering requirement for many materials. Brass is still the winner in this area considering that it has more shear strength than copper when subjected to the same load. But this strength is dependent on the composition of brass.
- Color: For copper, its reddish-brown color is a distinct quality that sets it apart from brass which has a golden-yellow color. Nevertheless, brass, the process of oxidation that produces patina in brass can change its color to reddish-brown and sometimes greenish color.
- Price: Considering budget is critical in any project and it significantly determines the material options available for many projects. With this said, copper can be a heavy metal and can even be heavier on the pockets seeing that it is more expensive than brass. Though brass prices also change depending on their constituents.
Brass vs Copper: Applications
The above-highlighted properties are good indicators of the applicable areas and specific use of both brass and copper. For instance, it is obvious that copper will make good electrical components due to its high electrical conductivity. Likewise, brass will be suitable for components that can resist wear and tear under applied loads.
- Wire & Cable: Due to its high electrical conductivity copper has always been a material of choice in the production of electrical cables and wires as it allows the flow of electricity with little resistance. It also ensures that you can get more power to your appliances while its anti-corrosion properties ensure the wires don’t degrade due to corrosion after a long period.
- Electronics & Related Devices: Smartphones, laptops, and TVs are a few of the electronics that use copper for their internal electrical conducting elements. Its high electrical conduction makes it suitable for transmitting electrical power to required components. Its corrosion resistance also ensures that these components remain unaffected by atmospheric moisture.
- Electric Motors: Automakers are finding great use for copper in their race to find sustainable transportation means for their customers with their electric vehicles. However, electric motors in both EVs and gasoline vehicles all rely on copper for their windings as it ensures the right amount of electricity gets to specific electrical components.
- Architecture: The built environment has relied on copper for so long, especially for areas in a building where water is usually a concern like roof gutters and downspouts. Also, it makes for good aesthetics with its shiny appearance considering that it has both antitrust and anti-tarnish properties.
- Antimicrobial: Due to its ability to disallow bacteria and the growth of dangerous microorganisms, copper serves as a suitable material for medical components, equipment, and tools. It ensures that the hygiene of these components is without question.
- Used as anti-biofouling: Over time, ship hulls can gather marine organisms like barnacles in a process known as biofouling. These organisms can reduce the efficiency of ships and vessels with a consequential increase in fuel consumption. The use of copper for marine vessels is used to mitigate against these biofouling processes as copper has anti-biofouling abilities.
- Means of Investment: Considering that copper is always in demand and is expensive makes it a good investment security. Many commodity exchanges accept it as a commodity of high value along with other precious metals like gold, silver, and platinum.
- Red Brass: Gunmetal is a type of brass that constitutes a higher quantity of copper than tin which accounts for its reddish color similar to copper and why it is also known as red brass. This version of brass has very high anti-corrosion properties and the reason is it is used for plumbing components like faucets, pipes, and control valves.
- Engraving Brass: Another version of brass with a high constituent of copper to zinc is engraving brass known as engraving brass. The combination of three properties, including anti-corrosion, hardness, and high formability makes it a suitable material for the production of bullet shells and casings.
- Free-Cutting Brass: With a high constituent of lead, free-cutting brass combines excellent machinability with strength and makes it suitable for producing fasteners like bolts and nuts.
- High Tensile Brass: The high percentage of zinc in this version of brass compared to its aluminum component makes it the material of choice for devices where high tensile strength is a requirement like in mold design.
Both materials have both similarities and differences and even for their similarities, one material will still outperform the other. Nevertheless, your choice for a specific use will depend on the details of your project.
III. Differentiating Brass from Copper: The methods.
Despite all the differences highlighted so far in this article, you might still need to find fail-proof ways of determining brass from copper especially when quality control and assurances are required. These requirements often require identification tests and sometimes constituents test to ascertain the material and its quality. Here are some standard ways of identifying both brass and copper starting with the easiest.
Visual inspection is often the first point of call when it comes to inspection and material identification. A critical part of this visual inspection is identification by color with brass and copper having their unique colors which you can use to differentiate them. For brass, even though the percentage of one of its constituents can change its color over time, still it often exists as a yellowish-gold colored material which can become more yellowish or reddish depending on the amount of zinc present. Copper is a standard reddish-brown in color which doesn’t change over time, and it is not difficult to spot.
Other Method of Identification:
If you still require further testing after visual inspection to separate copper and brass, then the following methods are standards that you can use.
1. Weight – Determining the weight of both brass and copper of the same volume can help you differentiate between the two. The weight of copper is more than that of brass and you can easily tell just from holding the same volume of both in your hand.
2. Magnetism – The magnetic properties of both brass and copper are seriously lacking. Consequently, if you introduce a magnet to both materials it will not stick but with brass, certain constituents can make it slightly magnetic.
3. Electric conductivity – Testing for electrical conductivity can easily separate brass from copper as copper is a better electrical conductor than brass. A simple circuit that consists of a battery and a light bulb with brass and copper as the conducting material. For brass, the light in the bulb has a lower intensity than for copper. You can also use a multimeter to ascertain the resistance of the materials since brass has more electrical resistance than copper.
4. Scratch Test – The harder material the more difficult it will be to scratch it. Hence, carrying out a scratch test on brass and copper helps to easily identify both as copper is softer and easy to cause an indentation, unlike brass which is harder and more difficult to cause an impression on it. Nevertheless, you should be cautious of the scratch method to avoid damaging the material.
5. Chemical Test – The chemical used in this test is often vinegar since it induces a tarnishing effect on both brass and copper. However, the rate of tarnish is often slower in brass and faster in copper which helps to separate them. Again, the tarnish color is different for both with brass turning brown and copper turning yellow.
6. Flame Test – Applying fire to both brass and copper will give different reactions. For brass, the color will turn yellow when it encounters fire while copper turns to reddish-orange on applying fire to it.
You should consider coated or painted brass and copper when deciding on the identification test to utilize. You might require a combination of these tests rather than using a single test to determine the materials.
IV. The selection of a suitable metal for your project.
Every project is unique in its requirements. These requirements often include moisture content, temperature, tensile strength, and electrical conductivity, to mention a few. However, careful consideration of the project will significantly determine the most suitable material between brass and copper.
If you have a project that requires a material with more aesthetic appeal, is strong, and is more affordable, then brass may be a suitable material in such a situation. However, if electrical conductivity is a critical requirement along with corrosion resistance and if budget is not of huge concern, then copper will be more suitable since it lasts longer in corrosion-prone areas.
Still, your decision may largely depend on your budget as it can limit or increase your options significantly including in rapid prototyping projects.
V. Which is better for your project Brass or Copper?
The quest to select the most appropriate material for a project is always important, especially before starting the project. However, choosing between two similar but different materials like brass and copper. Fortunately, their distinctive properties often help to easily decide the appropriate materials for specific projects. So, if you are looking for a material that is affordable and corrosion-resistant yet strong enough to withstand stress without experiencing serious wear and tear then brass will be ideal. But if your project requires a material with a high electrical conductivity that can withstand the effects of harsh weather then copper is your best bet. In the end, the cost of the material too will play a huge impact on the final decision.