Civilizations have come and gone, and the pages of history recount the use of several materials in the creation of tools, machines, and equipment that have helped elevate them at some points.
While many of these materials have long been forgotten, bronze and copper remain relevant despite the incredible technological strides since they were first discovered.
This post, however, is not only about their historical and present relevance but also a comprehensive look at their applications based on their differences despite appearing similar in many ways.
I. What are Bronze and Copper
You might fall into the trap of failing to tell bronze and copper apart at first glance, and you won’t be the last person to be tricked by their appearance. However, on careful examination of specific parameters and testing, it usually becomes evident that the two are indeed different in many ways. These differences give both materials uniqueness, certifying them as suitable for specific uses in several industries. But first, let’s find out what makes these materials exceptional and distinguishable from each other.
A. What is Bronze?
Bronze is not just a medal handed to the second runner-up in athletic competitions but an alloy that comprises several metals, especially tin and copper. Combining these metals makes bronze a notch stronger than some metals, particularly copper. It was at the center of the Greek civilization, giving them many technologies that made them a formidable nation at some point in history and leaving them with an era known as the bronze age. Tools and machines, weapons, and art edifices were constructed during this period entirely from bronze. Yet bronze remains relevant in our industries amid quantum energy and atomic science discoveries. And with its durability, strength, and flexibility, industry experts still believe it will continue to be relevant for many years. Bronze has a golden-brown color that is a beauty to behold. Combined with its strength, it makes for a versatile material for nearly any form of manufacturing, including rapid prototyping .
B. What is Copper?
With its reddish-orange color, copper has been around for many centuries serving as one of the most effective thermal conductors in the world. Its use as an electric material of choice by most electrical experts is not surprising considering that it has one of the highest electrical conductivity in the world, plus it is durable and corrosion resistant. Copper is a highly malleable material with applications in different industries dating back to the Mesopotamian and ancient Egyptian civilizations. Yet, it is still very relevant in today’s electrical, architecture, and plumbing industries. Its occurrence as a naturally pure material partially explains its extensive years of application since it requires little to no refinement.
II. What are the Differences Between Bronze and Copper
Differences aside, copper and bronze have proven indispensable over so many years and centuries. The reason is based on their uniqueness when evaluated using several engineering parameters. However, the differences between the two materials also account for their identification, which helps separate copper from bronze in any engineering production. But what are those properties that help identify these materials? Let’s take a look at them.
- Element Composition
Copper is a metallic element identified on the periodic table with its atomic number of 29, which explains why it is found as a naturally occurring material. Its symbol is Cu belonging to group eleven elements. On the other hand, bronze does occur naturally but is a combination of some metals, including copper, zinc, and nickel, making bronze an alloy.
- Corrosion Resistance
Both copper and bronze are resistant to corrosion which is more of a similarity than a difference. However, since bronze is an alloy of copper, it is expected to share some of its properties, like being corrosion-resistant. Moreover, the presence of other elements like zinc and nickel improves the anti-corrosion properties of bronze.
- Electrical Conductivity
Copper has one of the highest electrical conductivity ratings in the world, coupled with its durability, which makes it the material of choice for electrical products like wires, plugs, and sockets. While it is also durable and corrosion-resistant, bronze is a poor electrical conducting material compared to copper.
- Thermal Conductivity
Copper’s ability to conduct heat is also very high, which is why it is used for most heat exchangers and boilerplates where effective heat conduction is required. Bronze still lags behind copper in heat conduction, which is why it is not the material of choice for heat-conducting products.
- Melting Point
At a melting temperature of 913oC for bronze and 1080oC for copper, it is evident that copper takes longer to melt than bronze. This makes copper more suitable than bronze for use cases where high-temperature resistance is required.
Adding several metals and elements in bronze gives it more strength to withstand more load force and avoid indentation than copper. Hence, bronze will come out tops in scenarios where strength is required. For instance, a heavy load is required in the production of mold manufacturing machinery.
While the presence of some metals makes bronze harder than copper, other metals also contribute to making bronze lighter than copper. Copper will be sacrificed for bronze in weight-sensitive applications. This can include its application in architecture and artistic works like sculpting.
Bronze will last longer than copper under the same load and weather conditions due to bronze’s higher corrosion resistance than copper. This high anti-rust factor is due to certain elements like manganese that combine to form the alloy known as bronze, giving it its high durability and long lifespan.
Since copper is softer than bronze, machining copper requires less effort than when bronze is undergoing machining operations. Also, bronze’s hardness ensures that its machinability requires more complex machining tools like cutting, drilling, milling, and CNC machining than copper typically requires.
The ability to form a component or part of equipment by hot or cold rolling is easier with copper since it is highly ductile and malleable. However, bronze’s high strength and hardness inhibit its formability into new shapes and components.
The combination of various other elements to form bronze makes welding this alloy a bit difficult. However, since copper is a single metallic element, welding it is less stressful.
- Yield Strength
With a higher yield strength than copper, bronze can withstand more stress and strain caused by applied load without failing. On the other hand, copper yields easily, making it less suitable to resist certain pressure acting on it.
- Tensile strength
The bending caused by applied forces requires material like bronze with a significant tensile strength to endure the stress. With copper, which has a lesser tensile strength than bronze, enduring bending under loads will be unbearable.
- Shear Strength
Bronze has more rigidity to avoid material shear failure due to shear stress. With the low shear strength of copper, surviving specific shear stress may be impossible.
The color of these two materials is one of the confusing parts of distinguishing bronze and copper apart, as they can sometimes look very similar in color. The range of color of reddish-brown to dark brown for bronze often depends on the alloy composition. However, copper has a constant reddish-brown color that is distinct.
The demand in the copper market is higher than for bronze, which significantly reflects their prices as copper often costs more than bronze. Also, copper has no impurities in its natural state, which usually increases its demand and, consequently, its price. And because of its high electrical conductivity, it is often preferred in electrical works, increasing its demand, market value, and price.
The already itemized differences give the advantage to copper and bronze for specific uses in several industries, especially when considering them in critical stages like mold design. It also makes them unsuitable for other use cases where they are disadvantaged. Both bronze and copper have use case scenarios where they outshine the other material, mainly for engineering production. For bronze, its advantage depends on the dominant element that makes up the alloy, as this often increases or reduces a specific property. Let’s take a look at their various applications.
- 863 – Manganese Bronze: Manganese is an element that increases bronze’s anti-rust properties making it more suitable for use in marine components like bolts and nuts for vessels. It is also commonly used to manufacture propellers as it has high strength and corrosion resistance.
- 907 Tin Bronze: A bronze alloy with a high tin composition makes for a solid material and wear and tear-resistant bronze that can last very long. This property makes 907 tin bronze most suited to producing motors and motion components like bushings, bearings, and gears, where friction over time can lead to excessive wear and tear of the affected parts.
- 917 Tin Bronze: A further addition of tin will result in a bronze that can withstand high temperatures without losing its form, making it essential to produce heat-resistant parts. These parts can include boiling plates, steam fittings, and valve and pump parts.
- 955 Aluminum Bronze: Aluminum, in addition to bronze alloy, increases two properties – strength and corrosion resistance. Hardware used for marine purposes and water-prone areas, such as valves and pumps, is best produced with 955 aluminum bronze.
- 954 Aluminum Bronze: Another alloy of bronze known for its durability and strength is 954 aluminum bronze, applicable in manufacturing materials subjected to heavy friction since it is highly resistant to wear and tear. It is used in the production of bearings, bushings, and gears.
- Wire & Cable: Due to its outstanding electrical conduction properties, copper finds usage as the material of choice in the manufacture of electrical products such as cables and wires, switches, plugs, and other electrical connection devices.
- Electronics & Related Devices: Copper is also a primary component of several electronic devices and home appliances, including TVs, smartphones, fridges, and freezers.
- Electric Motors: The automotive industry uses copper extensively, especially for electric parts, including windings and fuse connectors, since it has a tremendous electrical conduction property.
- Architecture: For areas in buildings that are often subjected to water and high moisture content, such as the roof, architects often recommend copper-based building components to combat corrosion. Building components such as roof gutters and downspouts are some of these components. Copper also has the durability to last for a long time.
- Antimicrobial: In the health sector, such as hospitals, clinics, and labs, the use of copper for medical equipment and tools is very common, considering its antimicrobial properties.
- Anti-biofouling: Biofouling, a situation where marine organisms grow and stick to the bodies of vessels and ships, is often avoided using copper since it has anti-biofouling properties.
- Means of Investment: Copper finds application within the engineering domain and the financial world as it is precious and stable, two factors often considered priceless for investors. Hence, copper has been a means of investment for serious investors over the years, mostly because it has a high demand.
Copper and bronze have unique applications primarily due to their unique properties and characteristics. And their usage is extensive and varies across industries and sectors depending on the industry’s primary objective.
III. For Bronze and Copper, Which Is Better for Your Project?
Choosing between copper or bronze may be clear-cut depending on what you aim to achieve and the project’s budget. For instance, an electrical project that relies on the effective conductivity of electrical power will do better with copper since it has high electrical conductivity than bronze. Also, projects that require malleable and ductile parts for workability will often prefer copper over bronze. On the other hand, a project that requires high resistance to wear and tear due to heavy-duty force or friction-causing motion will require a bronze material for its strength and durability. Ultimately, your specific needs for a project ranging from ductility, aesthetics, and conductivity, will significantly determine your choice between the two materials.