Brass is one of the most commonly used man-made metals in the world. For the most part, people are familiar with brass through applications like door locks or musical instruments. These applications display the versatility of the metal. Brass consists of copper and varying amounts of zinc and other metals. Depending on the other metals present in the alloy, brass’ properties begin to vary.
There are over 60 different types of brass available on the market. The staggering number of options available can make it a little difficult for those who are not completely familiar with brass to choose which one they will need. Fortunately, choosing the type of brass you need is easy if you know exactly how you want to use it.
Respected copper and brass suppliers like Rotax Metals typically carry a wide range of brass options for buyers to choose. Here are some of the most common types of brass sold by suppliers and their best uses:
Alloy 260 – 70/30 Brass
Alloy 260, more commonly known as “70/30 brass”, is the most common type of alpha brass used today. The ratio of brass to zinc is 7:3, hence the common name of this type of brass. As zinc dissolves into the copper during manufacturing, the metals combine into a solid solution that boasts a uniform atomic composition. The result is a softer and more ductile than other types of brass. Don’t mistake “softer” for fragility. 70/30 brass is boasts fantastic durability considering how ductile it is. The unique ratio of this type of brass also means that it is less susceptible to corrosion caused by dezincification.
Alloy 280 – Muntz Metal
Alloy 280, more commonly known as Muntz metal, is an alpha-beta type of brass. It is named after George Muntz, a British metal-roller who patented the brass back in 1832. The alloy is made using a mixture of 60 percent copper, 40 percent zinc, and traces of iron. Muntz metal is known for its stronger, “springier”, and more rigid when compared to other types of brass. Although there is a decrease in corrosion resistance compared to alloys with less zinc, it is still considered a corrosion-resistant alloy. Some of the most common applications for Muntz metal include brass springs, electrical sockets, plumbing parts, fasteners, and corrosion-resistant machine parts.
Alloy 353 – Leaded Brass
Alloy 353, more commonly known as leaded brass sheets and plates, is a type of beta brass. This type of brass has more than 45 percent zinc in it. However, the inclusion of lead in the alloy allows it to adopt atmospheric corrosion resistance and increases the machinability of the entire sheet. Known for its stiffness, it is also ideal for free-cutting. It is commonly used as machine parts that are subjected to friction such as nuts and gears. The brass is also used as a blanket for engraving purposes in clocks and watches. Leaded brass also boasts a good return value as scrap. This allows the alloy to be quite competitive with steel in terms of net cost.
Alloy 385 – Architectural Bronze
Alloy 385, more commonly known as architectural bronze, is often found in brass angles. It is often compared to Alloy 360 (also known as free cutting brass). The key difference here is that architectural bronze has les lead in it. The unique blend of metals makes architectural bronze good at resisting corrosion. This alloy is prized for its machinability and how it is easy to process via hot forging and pressing, and hot forming and bending. As its name would suggest, it is mostly used in architectural applications like trims and hinges. Artists who sculpt with metals also favor alloy 385 due to how easy it is to shape.
Alloy 464 – Naval Brass
Alloy 464, more commonly known as naval brass, is one of the most common types of alpha-beta brass. Naval brass boasts 59 percent copper, 40 percent zinc, 1 percent tin, and lead in trace amounts. This unique composition makes naval brass remarkably hard and strong. As you may have guessed from its name, naval brass is primarily used in seafaring vessels. The presence of tin and lead in the alloy helps protect the brass from the corrosive effects of saltwater. Although the main use for naval brass is in marine applications, it is also used in the industrial sector. Welding rods, valve stems, exchanger tubes, and condenser plates are some of the industrial applications of naval brass.
Questions to Ask Yourself to Help You Choose the Right Type of Brass
The first thing you need to do if you have a project that involves the use of brass is to figure out where to buy brass. This is relatively easy since many renowned brass suppliers deliver nationwide. Once you’ve settled on a supplier, you’ll need to figure out which type of brass you need.
Most brass suppliers, like Rotax Metals, will have more than just the five types of brass mentioned above. Many of these different types of brass share similar properties, but also offer different specializations. This can make it difficult to pinpoint the exact type of brass you need. If you are having difficulty identifying the best type of brass for the job, try answering the following questions:
What are the mechanical properties I need from the final product?
Try to imagine the final product made with the brass you’ve built. How will that product be used? Depending on its use, you will need different properties present in the brass you buy. Ask yourself if there is a specific tensile strength or yield strength you need from the final product. Will elasticity be a concern when manufacturing the final product? Asking yourself these questions will usually help you narrow down your choices to a handful of options.
What degree of machinability do I need for this project?
Machinability refers to how well a certain metal is cut into its final form and size via a controlled material removal process. Depending on how you plan to process the brass you purchase, you may prefer brass sheets that offer higher machinability or you may require sheets that boast lower machinability. Alloy 360 is often considered the benchmark for machinability of brass. Machinability isn’t just about how easy it makes it for you to process your brass. Higher machinability tends to be desirable since it can have a direct impact on the cost efficiency of your project.
Do I need to achieve a certain aesthetic with the final product?
Since brass is made of different types of metals, you can expect certain chemical reactions to occur as you process it. There may be times when you the brass used changes in color during your manufacturing process. In most cases, this is not much of a problem if you plan to add a coat of primer and paint over the final product. However, there will be times when you will want to retain the alluring color of brass. You’ll want to research on how a particular type of brass may react to how you process it before buying it.
Once you’ve answered these three simple questions, you should have been able to narrow down your choices to around three different types of brass. This should make it easier for you to compare the differences between them and make the best choice for your project. If you are still having trouble deciding, do not hesitate to share these answers with the supplier’s sales team. They can easily draft a shortlist of recommendations for you and steer you towards the best type of brass for your needs.
Extrusion is a metalworking technique that involves pushing a material through a die to create objects of fixed cross-sectional profiles. Manufacturers often prefer this technique traditional casting because of its ability to create complex cross-sections. Since the whole process relies on compression and shear forces, it is perfect for working brittle metals as well. Generally, all malleable and ductile metals can be extruded. Their unique properties enable them to conveniently flow through the die even with minimal compression. It can therefore be presumed that the most ideal metals to work using this technique are those with naturally high malleability, such as copper alloys. 