Composition of Common Brass Alloys
Brass is a metal alloy that is always made with a combination of copper and zinc. By varying the amount of copper and zinc, brass can be made harder or softer. Other metals—such as aluminum, lead, and arsenic—may be used as alloying agents to improve machinability and corrosion resistance.
How Different Alloys Change the Properties of Brass
By adding different metals to brass, it is possible to change its properties. It can become yellower, harder, softer, stronger, or more corrosion-resistant, depending upon its chemical composition. For example:
Brass is usually a warm golden color. The addition of 1 percent manganese, however, will turn brass to a warm chocolate-brown color, while nickel will make it silver.
Lead often is added to brass to make it softer and thus more malleable.
Arsenic may be added to make brass more stable in certain environments.
Tin can help to make brass stronger and harder.
Types of Brass
Common Brass Alloys
There are many different types of brass, each with a slightly different chemical composition. Each type of brass has its own name, qualities, and uses. For example:
Red brass, not surprisingly, is warmer in color than other brasses. It also is a particularly strong type of brass.
Cartridge brass (also referred to as 260 brass and yellow brass) is best known as an ideal metal for shell casings. It is most often sold in sheet form and easily formed and worked into desired shapes.
330 brass is particularly useful in tubing and poles because it is both workable and machinable. Fire poles are a common use for 330 brass.
Free machining brass, also called 360 brass, is relatively high in lead, making it easy to cut and shape. It often is used to make items such as rods and bars.
Naval brass, also called 464 brass, is highly resistant to corrosion and thus ideal for use in seawater.
Corrosion Resistance of Brass
Contact with an amine, a compound derived from ammonia, is a common cause of brass corrosion. The alloy also is susceptible to corrosion through the process of dezincification. The more zinc brass contains, the more it can be impacted by zinc leaching out of the alloy, causing it to become weaker and more porous. The National Sanitation Foundation International (NSF) standards require brass fittings containing at least 15% zinc to be resistant to dezincification. Adding elements such as tin, arsenic, phosphorus, and antimony can help achieve this effect, as can reducing the amount of zinc to less than 15%. Brass with less than 15% zinc is known as red brass.
Naval brass, which is used in seawater, actually has 40% zinc, but it also contains 1% tin to reduce dezincification and make it more resistant to corrosion.
Uses of Brass
Brass is a popular metal for applications that are both practical and decorative. Items like door handles, lamps, and ceiling fixtures like lights and fans are examples of practical uses that also serve a decorative purpose. Aside from being attractive, brass also is resistant to bacteria, making it that much more useful for fixtures like door handles that multiple people touch frequently. Some uses, such as figures atop bedposts, are strictly decorative.
Many musical instruments also are made of brass because it is a very workable metal and can be formed into the sorts of precise shapes necessary for horns, trumpets, trombones, and tubas. These instruments, collectively, are commonly known as the brass section of an orchestra.
Because of its low friction and resistance to corrosion, brass also is popular hardware for plumbing fixtures and other building supplies. Pipe fittings, nuts, and bolts are often made of brass to take advantage of its characteristics. Shell casings for ammunition also are a popular use for brass, largely because of its low friction.
Brass also is highly ductile, meaning it can be formed into a lot of shapes, making it a popular alloy for use in precision instruments, such as gauges and clocks.
Compositions of Common Brass Alloys
The chart below summarizes the composition of a number of commonly used brass alloys:
UNS No. |
AS No. |
Common Name |
BSI No. |
ISO No. |
JIS No. |
Copper % |
Zinc % |
Lead % |
Other |
| C21000 | 210 | 95/5 Gilding metal | – | CuZn5 | C2100 | 94–96 | ~5 | – | |
| C22000 | 220 | 90/10 Gilding metal | CZ101 | CuZn10 | C2200 | 89–91 | ~10 | – | |
| C23000 | 230 | 85/15 Gilding metal | Cz103 | CuZn20 | C2300 | 84–86 | ~15 | – | |
| C24000 | 240 | 80/20 Gilding metal | Cz103 | CuZn20 | C2400 | 78.5–81.5 | ~20 | – | |
| C26130 | 259 | 70/30 Arsenical brass | Cz126 | CuZn30As | C4430 | 69–71 | ~30 | Arsenic 0.02–0.06 |
|
| C26000 | 260 | 70/30 Brass | Cz106 | CuZn30 | C2600 | 68.5–71.5 | ~30 | – | |
| C26800 | 268 | Yellow brass (65/35) | Cz107 | CuZn33 | C2680 | 64–68.5 | ~33 | – | |
| C27000 | 270 | 65/35 Wire brass | Cz107 | CuZn35 | – | 63–68.5 | ~35 | – | |
| C27200 | 272 | 63/37 Common brass | Cz108 | CuZn37 | C2720 | 62–65 | ~37 | – | |
| C35600 | 356 | Engraving brass, 2% lead |
– | CuZn39Pb2 | C3560 | 59–64.5 | ~39 | 2.0–3.0 | – |
| C37000 | 370 | Engraving brass, 1% lead |
– | CuZn39Pb1 | C3710 | 59–62 | ~39 | 0.9–1.4 | – |
| C38000 | 380 | Section brass | Cz121 | CuZn43Pb3 | – | 55–60 | ~43 | 1.5–3.0 | Aluminum 0.1-0.6 |
| C38500 | 385 | Free cutting brass | Cz121 | CuZn39Pb3 | – | 56–60 | ~39 | 2.5–4.5 | – |
Forging Brass Rods
Forging Brass Rods, Leaded Brass Extrusion Fittings, High Tensile Round Brass Rods, Forging Free Cutting Brass Bars, Brass Sections & Profiles, Profile and Flat Brass Rods, Round Extrusion Rod Brass , Brass Hollow Rods free machining brass or leaded brass Forging Brass Rods Use: It is mainly used for manufacturing forged components and pressing materials […]
Leaded Brass Rods Extrusion Fittings
Leaded Brass Rods Extrusion Fittings, Free Machining Brass Rods, High Tensile Round Brass Rods, Forging Brass Rods, Free Cutting Brass Bars, Brass Sections & Profiles, Profile and Flat Brass Rods, Round Extrusion Rod Brass , Brass Hollow Rods free machining brass or leaded brass Leaded Brass Rods Extrusion Fittings, Free Cutting Brass Round Rods, Free […]Common Brass Alloys
High Tensile Brass Rods
High Tensile Brass Rods, Lead Free Brass Rods, Forging Brass Rods, Free Cutting Brass Bars, Brass Sections & Profiles, Profile and Flat Brass Rods, Round Extrusion Rod Brass , Brass Hollow Rods Rectangle Bars Rectangle Brass Rod High Tensile Brass Rods Use: High Tensile Brass Rods are also know as Manganese Brass and is used […]Common Brass Alloys
Free Machining Brass Rods
Free Machining Brass Rods, High Tensile Round Brass Rods, Leaded Brass Rods, Forging Brass Rods, Free Cutting Brass Bars, Brass Sections & Profiles, Profile and Flat Brass Rods, Round Extrusion Rod Brass , Brass Hollow Rods free machining brass or leaded brass Free Cutting Brass Round Rods, Free Machining Brass Rods Use: Free Cutting Brass […]Common Brass Alloys
