Machining of Parts: Which is Better, Brass or Bronze?

It is common to use bronze and brass in the machining of parts, two metals that, while similar in nature, must be differentiated to be used correctly. Comparing their features, attributes and benefits is what this article is all about.

We need to have a clear understanding of what brass and bronze are. This section aims to give the reader a clear understanding of what each metal is.

What is Bronze?

Cupro-strontium is the primary constituent of bronze, which is a metal alloy. Known as the Bronze Age, this metal dates back to 3500 BC, when the Sumerians first used it. It is classified as a copper alloy based on its mechanical properties and the specific alloying elements it contains.

By using various elemental compositions, the properties and characteristics of bronze can be improved. Manganese, nickel, silicon, lead, antimony, and zinc are just a few examples of these metals. Because of this, there is a wide range of bronze grades for designers to choose from. Although cast iron is more brittle, bronze is less so than cast iron, which is typically reddish-brown or gold in color and more brittle.

What is Brass?

The main components of brass are copper and zinc. Brass also contains tin, iron, aluminum, lead, silicon, and manganese. Brass has a wide range of electrical and mechanical properties thanks to its elemental composition. Zinc improves the ductility and strength of copper by enhancing the zinc content in brass. The more zinc a brass alloy contains, the more pliable and strong it becomes.

Depending on the zinc/copper ratio, brass can come in a variety of colors, from bright gold to silver. It can be compared to zinc in terms of ductility and low friction when machining other metals. In addition, because of its gold resemblance, brass is frequently used in decorative applications.

How can you tell brass and bronze apart?

Color is one way to tell brass and bronze apart. Brass is usually yellow, like dull gold, while bronze is generally a reddish brown. But the key difference between these sturdy, versatile copper alloys lies in their composition.

What is brass made of?

Brass is an alloy of copper and zinc. Brass can also contain small amounts of other metals, like tin or lead. It is non-ferrous, meaning it contains no iron. Brass is more malleable than bronze, and with a low melting point of 900°Ccan be easily cast into molds. Different ratios of copper and zinc will result in different types of brass. The higher the proportion of zinc, the stronger and more flexible the brass. The more copper brass contains, the more electrically conductive will be. Red brass, or rose brass, generally has a higher copper composition, about 85 percent, and therefore a redder or more copper appearance. Yellow brass looks more like gold and typically contains only about 60 percent copper.

What is brass used for?

The use of brass dates to 500 CE. Brass does not rust making it ideal for locks, doorknobs, and other outdoor uses. Brass can also be used for plumbing and piping, electrical connectors, and for aviation.

Because it resists tarnishing, brass has a long history of decorative use. Brass containers, housewares and personal decorations such as brooches were hugely popular in the ancient world, and 18th-century brass buttons, tobacco boxes, candlesticks, keys, and umbrella stands are prized antiques today. Historically, brass was also used for scientific instruments including astronomy and navigation.

Brass isn’t magnetic, so if you want to find out if that antique brass lamp or bedframe you’ve inherited is solid brass or just brass plate, try running a magnet over it. If you feel a pull, it’s likely brass-plated iron.

Brass resists corrosion and can be used for nautical applications. Naval brass, a mixture of 59% copper, 40% zinc, and 1% tin, was specifically developed for maritime use.

Brass is widely used for wind instruments, such as trumpets, tubas, horns and trombones.

Brass is most often used for musical instruments, including trumpets, tubas, horns, and trombones, due to its flexibility and acoustic properties. In fact, the quality of sound your horn or trumpet makes is largely determined by the type of brass used for the instrument. Yellow brass, which contains more zinc, produces a lighter sound than gold brass, which contains more copper. Red brass produces a warm tone but doesn’t project sound as well because it contains less zinc.

What is bronze made of?

Bronze is an alloy made of copper and, primarily, tin. Pure (or commercial) bronze consists of 90 percent copper and 10 percent tin. Bronze has a higher melting point than brass, at 950°C, and is more brittle. Bronze dates to about 3000 when the introduction of tougher, better-lasting bronze tools and weapons marked a turning point in human development.

What is bronze used for?

Brass and bronze resist saltwater corrosion and are ideal metals for use in maritime applications.

Because bronze, like brass, is resistant to saltwater corrosion, it’s ideal for marine applications such as ship propellors, rudders, portholes, center-boards, and engine parts. Some of the earliest known warships used bronze armored rams to destroy enemy boats. Bronze, brass, and other copper alloys are almost exclusively used in the electrical systems and in the engine rooms of today’s more sophisticated merchant and naval ships.

Like brass, bronze creates less friction than other metals, and is often used for non-sparking tools needed on oil rigs, chemical plants, and other areas where flammable or combustible materials are present.

Exposure to air oxidizes the bronze’s copper components over time resulting in a classic green, blue, and brown patina.

Bronze is also widely used for statues and sculptures. The tallest statue of the ancient world, the Colossus of Rhodes, was constructed from bronze. Today’s tallest sculpture, the Statue of Unity, standing at 182 meters (597 ft), is bronze clad.

Bronze medals are traditionally awarded to competitors finishing third place in athletic competitions, and there’s evidence that bronze medal winners may actually be happier than those who win silver.

Bronze with a high tin content (between 20-25 percent) is called bell-metal and is used exclusively to make bells. The high tin content in bell-metal increases a bell’s resonance.

What is galling and why does it matter?

Galling is caused when metal surfaces rub and adhere together, causing wear and damage to parts and surfaces. The more ductile (or pliant) a metal is, the more likely it is to gall. Brass and bronze are popular choices for bearings and bushings, especially in marine environments, because these tough copper alloys resist galling, resulting in decreased damage and better performance of moving components over time.

Bronze vs. Brass: What are the Differences?

In this section, the differences and similarities between bronze and brass are discussed.

Composition of the Elements Between Bronze and Brass

The elemental composition of bronze and brass can be used to distinguish the two metals. Bronze, is made up of copper (Cu) and tin (Sn) as its main components, and it also contains the following components: 

• Aluminum

• Lead (Pb)

• Antimony

• Nickel (Ni)

• Phosphorus (P)

• Silicon (Si)

• Sulfur (S)

• Cobalt

• Chromium

• Zinc

Brass, on the other hand, is a simple copper-zinc alloy. Copper (Cu) and zinc (Zn) are the primary elements in nature, but depending on the alloy form, they also contain the following components:

• Tin (Sn)

• Sulfur (S)

• Silicon (Si)

• Phosphorus (P)

• Nickel (Ni)

• Lead (Pb)

• Iron (Fe)

• Antimony (Sb)

• Aluminum (Al)

Bronze or Brass: Which is Better?

Bronze or Brass, Which has Better Corrosion Resistance

The level of corrosion resistance of brass and bronze can also be used to compare the two metals. Copper (Cu) in bronze causes it to oxidize in the air, resulting in a mottled patina. As a result, bronze will not corrode as quickly in saltwater environments, which is why this is an important consideration. Bronze develops a disease known as “bronze disease” when it comes into contact with chlorine compounds. Bronze becomes more vulnerable to corrosion as a result of this disease, and the copper alloy gradually degrades over time. For boats and marine parts, bronze is a popular choice because of its resistance to saltwater corrosion.

Brass, on the other hand, is designed to withstand corrosion, particularly in seawater, because of the galvanic charge. When brass is subjected to corrosion, it loses its zinc content, resulting in a process known as dezincification, which leaves only copper. While going through this process, the color of the brass changes from yellow to pink. The bronze layer can be coated to stop this process.

Bronze or Brass, Which is More Electrically Conductive.

Copper is the primary metal in both of these alloys. Most metals’ electrical conductivity is measured against copper as the gold standard. Brass and bronze have relatively low electrical conductivity compared to the other metals we examined. If bronze and brass are made primarily of copper, they should have nearly the same conductivity as copper. Due to the presence of various other elements, this isn’t the case. It is because of this that the electrical conductivity performance of bronze and brass is degraded. Typically, brass is only 28% as conductive as copper. Some bronzes are as low as 7% and as conductive as copper.

Bronze or Brass, Which has Better Thermal Conductivity

If the material has high thermal conductivity, it can be used in thermal applications. To determine how much energy can be transferred through the material and at what rate, this information is useful. Because brass has a much higher thermal conductivity than bronze, the latter is a better choice for radiator construction. When it comes to thermal applications, bronze can be used, but its counterpart – brass – will be preferred over bronze.

Bronze or Brass, Which has Better Higher Melting Point

Both bronze (315 – 1080 °C) and brass (809 – 1030 °C) are easily cast metals with a higher melting point. It is critical to know the melting point of brass or bronze when making a material selection for a project. This is due to the possibility of a component failure at the point of melting.

For something to change from solid to liquid, it must first reach its melting point. At this point, the material is ready to be cast into a variety of shapes. The desired mechanical properties must be taken into account when using brass or bronze for shape casing. Brass is more likely to be useful for a decorative project, while bronze is more likely to be useful for a more robust one.

Bronze or Brass, Which has Better Hardness

The response of a material to local surface stress and the material’s response to dent, scratch, and many more is measured by the hardness of the material. The Brinell hardness scale is one of several hardness measures that exist in this context. An indenter is used to measure a material’s response to a predetermined force. A bronze object gets a score between 40 and 420 on this scale, while a brass object gets a 55-73 score.

A comparison of hardness between bronze and brass reveals that bronze is, on average, slightly more difficult to work with. Bronze is more brittle than brass because it is a harder material, and this rule holds. The durability and strength of the material are critical considerations for a project. But if workability is a requirement, brass is far preferable to bronze.

Bronze or Brass, Which is Lighter Weight

Brass and bronze are both metals, so when comparing their weight, water can be used as a baseline for specific gravity. It is then compared as a fraction of the heavier or lighter density for brass and bronze. We found bronze to be the heaviest of the metals, weighing in at a density ranging from 7400 to 8900 kg/m3. Brass, on the other hand, weighs between 8400 and 8730 kg/m3 based on its elemental composition.

Bronze or Brass, Which is More Durable?

The material can remain functional over its half-life without the need for excessive repair or maintenance that determines the material’s durability. Despite its strength, bronze is a brittle metal that is difficult to work with. In addition, bronze can withstand water, making it resistant to corrosion from water. In contrast, brass is strong but less long-lasting than bronze. As a result, it is fairly resistant to corrosion and cracking.

Bronze or Brass, Which Has Better Machinability

Machinability is a measure of a metal’s ability to withstand machining processes like stamping, milling, turning, and more. A material’s machinability score has a significant impact on the type of machining that can be performed on it.

A machinability percentage is calculated by comparing a material’s machinability to a reference material that has a rating of 100%. Brass and bronze, which are more difficult to machine, have a percentage below 100. There are a few copper alloys that have been specifically developed for machining, such as the brass alloy C360. Brass is more malleable than bronze, making it a better material for jewelry making. Even though brass is supposedly hard, bronze, an alloy of copper and tin, is much softer than brass. Brass is more malleable than other metals, making it easier to work with in terms of shaping, cutting, and filing.

Bronze or Brass, Which Has Better Weldability

In terms of welding, bronze and brass are both usable. As a general rule, brass alloys containing lead are more difficult to weld than brass alloys with the lower zinc content. Brass with a zinc content of 20% or less is considered good weldable, while brass with a zinc content of 20% or more is considered fair weldable. Cast brass metals, on the other hand, can only be marginally welded.

On the other hand, the weldability of unleaded bronze alloys is fair, but they are vulnerable to cracking under stress. Leaded phosphor bronze, on the other hand, can be precisely welded with a SMAW.

Bronze or Brass, Which Has Better Yield Strength

According to this definition, the maximum stress at which metal will permanently deform is known as its yield strength. In a comparison of the two metals, brass has a higher yield strength than copper. A bronze yield strength of 69.0–800 MPa (10,000–116,00 psi) and a brass yield strength of 34.5–683 MPa (5,000–99,100 psi) back up this claim.

Bronze or Brass, Which Has Better Tensile Strength

In the manufacturing industry, the strength of the material is a major consideration when deciding on what type of material to use. The increased tensile strength that bronze and brass show when cold worked, or in the case of brass, when more zinc is added, makes them highly sought-after metals.

The tensile strength of annealed bronze measures 50 Ksi (350 MPa), whereas the cold-rolled-tempered version of the metal has an even higher tensile strength of 92 Ksi (635 MPa). When annealed and cold-rolled tempered, its tensile strength ranges from 53 kg/cm2 (365 kg/cm2) to 88 kg/cm2 (607 kg/cm2).

Bronze or Brass, Which Has Better Shear Strength

Strength against the type of yield or structural failure, particularly when the metal fails in shear. The term “shear load” refers to a force that causes material or component to slide or fail in a plane perpendicular to the force’s direction. While bronze has the lowest shear strength, brass has the highest, measuring from 35000 pounds per square inch to 48000 pounds per square inch.

Color Comparison Between Bronze and Brass

Using color is a quick and easy way to tell the difference between bronze and brass. The color of bronze can be described as reddish-brown. When other elements are incorporated into the bronze mixture, this property may be slightly altered. It doesn’t matter how much bronze has changed; it’s still easy to tell the two apart. Brass, on the other hand, tends to have a muted yellow hue that’s a lot like dull gold in appearance. This makes it a great material for furniture and fixtures because of this.

Bronze or Brass, Which is Less Cost?

The copper content of a piece of bronze or copper can have a significant impact on the final product. In both alloys, the price depends on the amount of copper present. Bronze, on the other hand, tends to be more expensive than brass. This is due to the copper content and the manufacturing process that goes into bronze.

Application of Brass and Bronze

Bronze

Bronze is available in a wide range of alloys and forms, and it can be used for a wide range of purposes. Before stainless steel became widely used in ship and boat fittings, bronze was widely used for coins. Bronze is still used in ship propellers and underwater bearings. In the modern world, bronze is used for bearings, springs, bushings, automobile transmission pilot bearings, small electric motor bearings, and many other applications.

When struck against a hard surface, bronze tools such as mallets, hammers, and wrenches don’t produce any sparks. Bronze wool for woodworking is also made from them. Sculptures, musical instruments, and electrical contacts can all benefit from bronze. Bronze alloys have a wide range of characteristics, including the following:

Manganese Bronze

Known for its corrosion resistance and high strength, this bronze alloy is a popular choice for the aerospace, fastener, marine, and oil and gas industries. Manganese bronze contains small additions of manganese, iron, and aluminum, plus lead for lubricity, anti-seizing, and bonding. Like the aluminum bronzes, they combine high strength with excellent corrosion resistance. Manganese bronze bearings can operate at high speeds under heavy loads but require high shaft hardness and nonabrasive operating conditions. Because of its strength and longevity, it is an excellent choice for heavy-duty applications. The following can be made with Manganese Bronze:

• Landing Gear Parts

• Strut Bushings

• Screw Machine Parts

• Bearings

• Bushings

• Gears

• Lead Screw Nuts

Tin-Bronze

Tin’s primary function in these bronze alloys is to strengthen them. Tin bronze is extremely strong, hard, and ductile. This combination of characteristics provides them with a high load-carrying capacity, good wear resistance, and the ability to withstand the pounding. The alloys are known for their resistance to corrosion in seawater and brines. Tin bronze has excellent corrosion resistance, especially when exposed to seawater. It has good wear and fatigue properties and can be machined to some extent. The following can be made with the alloy:

• Bearings

• Gears are bronze plated.

• Bushings and other marine hardware

• Pump parts, such as piston rings and pump impellers

Aluminum Bronze

Aluminum bronze alloys are popular because of their high strength and excellent corrosion and wear resistance. C95400 aluminum bronze is a popular cast aluminum bronze with high strength and excellent wear and corrosion resistance. Although this alloy is supplied in its cast condition, it can be heat-treated to enhance its mechanical properties for more demanding applications including:

• Gears

• Bushings

• Bearings

• Preserving food (baskets/hooks)

• Components of valves

• Machine Tool Ways

Silicon Aluminum Bronze

Silicon Aluminum Bronze is a well-known relative of Aluminum Bronze alloys, with benefits ranging from high mechanical properties to unrivaled anti-corrosive properties, anti-galling strength, and fatigue resistance. It is primarily composed of silicon, aluminum, and copper. Silicon Aluminum Bronze can be used for the following applications:

• Landing gear parts

• Strut Bushings

• Rock bit bearing bushings

• Valve guides

• Safety belt assemblies

• Pole line hardware

• Valve and pump components

• Cams

• Hooks

• Forged machined components

Besides, Nickel Aluminum Bronze, Silicon Aluminum Bronze, Silicon Bronze, Silicon Iron Bronze, Nickel Silicon Bronze, Nickel Silver Bronze, Nickel Tin Bronze, Leaded Bronze, Phosphor Bronze, and Lead-Free Bronze also belong to the family of bronze alloys. For more information, please look into Bronze’s Wiki Page.

Brass

Brass can be used in many different industries. Because of its gold resemblance, it is frequently used as a decorative part. Brass is an ideal material for making musical instruments because of its long-term durability and ease of processing. Corrosion-resistant plumbing pipes and tubing can be made with this material. Because of its high electrical conductivity, brass is commonly found in electronic devices. Brass is used in a variety of mechanical components, including the M-16 rifle’s shell casting, gears, and bearings, to name just a few. Brass alloys with specific properties have a wide range of uses.

Red Brass

Red brass is the most durable of all metals for the plumbing industry and commercial water pipe applications. It is excellent for resistance to dezincification and season cracking, which most high copper brasses are known for. About 95% copper and 5% zinc are used to make this alloy of brass. Easily formed or hammered into the desired shape, Red Brass is a soft brass alloy. Red brass is also specified for underground service lines since it offers great corrosion resistance to all types of potable water and has moderate strength and good retention of spring properties.

For example, red brass C352 has a small amount of arsenic added to the alloy to prevent chlorinated water from leaching the zinc from your plumbing products, which eventually leads to the weakening and cracking of your plumbing products. The Red Brass C352 can be used for the following purposes:

Formed into fittings and nipples for carrying water in commercial plumbing and OEM applications. low-cost bearing materials. Fascia is a part of an architectural design.BadgesHardware for boats and shipsHandles for the DoorsDecorated edgingBrass etching engraving BrassC35600 or C37000 is the common designation for engraving brass, which has a lead content of 1% to 2%. So, as its suffix suggests, its primary use is to engrave plaques and nameplates, in essence. Engraving brass can be used for the following purposes: Brass Rim Free Cutting Hardware for Builders, Gear Meters, and Clock Components.

Yellow Brass

Yellow brasses have relatively good corrosion resistance, are moderately high in strength, and in some forms, have very good ductility. They are available in many forms including rod, bar, sheet, plate, and more. For example, yellow brass C260 is a combination of copper and zinc, It is an attractive material with a smooth, yellow brass finish and it can have a polished or brushed (satin) finish. C260 Brass can be used in corrosive environments. C260 Brass forms a thin protective patina ( layer ), which, unlike steel and iron, will not rust when exposed to the atmosphere. It has excellent cold workability and is used extensively in the automotive industry, also in the manufacturing of plumbing, hardware, and ammunition components. Yellow brass can be used for the following applications:

• Automotive: Odometer Contacts, Heater Cores, Thermostats, Electrical Connectors, Radiator Cores, Radiator Tube, Radiator Tanks, Tanks

• Builders Hardware: Odometer Contacts, Heater Cores, Thermostats, Electrical Connectors, Radiator Cores, Radiator Tube, Radiator Tanks, Tanks

• Consumer: Snaps, Planters, Fireplace Screens, Etched Articles, Bird Cages, Coinage, Chain Links, Pen/Pencil Inserts And Clips, Syringe Parts, Watch Parts, Costume Jewelry, Buttons, Shells – Electrical Sockets, Lamps

• Electrical: Terminal Connectors, Flashlight Shells, Lamp Fixtures, Reflectors, Screw Shells

• Fasteners: Pins, Rivets, Fasteners, Grommets, Eyelets, Screws

• Industrial: Air Pressure Conveyor Systems, Sound Proofing Equipment, Springs, Chain, Bead Chain, Tubing For Instruments And Machines, Heat Exchangers, Pump Cylinders, Wire Screens, Pumps, Liners, Power Cylinders

• Ordinance: Ammunition Cartridge Cases, Mechanical Housings For Lighters, Shells – Mechanical Housings For Ammunition, Ammunition

• Plumbing: Fittings, Bathroom Fixtures, Plumbing Accessories, Faucet Escutcheons, Traps, Plumbing Brass Goods

• Architecture: Grillwork

• Other: Stencils, Washers

Free Machining Brass

C-360 brass is the most versatile and commonly used copper-alloy bar stock used in both the North and South American Markets, second only to copper itself! It is used to make a variety of screw machine products. Its 100 percent machinability stems from a favorable interaction between the material’s basic structure and a few percentages of lead. The result is an alloy with good engineering properties and the ability to be machined at an extremely low cost. It is frequently used in the following contexts:

• Builders Hardware: Lock Bodies, Hardware, Fittings

• Consumer: Hot Combs (To Straighten Hair)

• Fasteners: Bolts, Nuts, Screws

• Industrial: Faucet Components, Pneumatic Fittings, Fluid Connectors, Automatic Screw Machine Parts, Unions, Adapters, Screw Machine Products, Gauges, Valve Seats, Valve Trim, Valve Stems, Nozzles, Pinions, Gears

• Plumbing: Plumbers’ Brass Goods, Faucet Stems, Faucet Seats, Plumbing Fittings.

How to Distinguish between Brass and Bronze

Brass usually has a muted yellow shade, much like dull gold, which makes it a good material for furniture and fixtures. Bronze, on the other hand, looks almost always like a reddish-brown. This characteristic may slightly change when other elements are added to the mixture, but it’s still easy to tell them apart. If you can’t tell them apart with the naked eye, then we can try some other ways.

Use a salt-and-vinegar paste to thoroughly clean the two metals before attempting to identify them. Patina, the dark or green layer that forms on bronze and brass over time, accounts for this. Because of this patina, it is difficult to tell the difference between the two metals. Salt, flour, and white vinegar should be mixed to form a thick paste for thorough cleaning. Then use a sponge to apply the paste to the metal and rinse it off with hot water.

See if the metal is a reddish-brown color. Once the metal has been cleaned to reveal its true color, check to see if it has a reddish-brown hue. Brass, on the other hand, is made of copper and tin, so it has a yellowish hue. Holding a variety of metals will help you see the color more clearly, making it easier to identify. If the metal is reddish-brown, it is likely bronze.

Because of its copper and zinc elemental composition, brass appears yellowish at first glance. The brass-yellow color appears duller and less vibrant in comparison to the gold, which appears more yellow. It’s brass if the metal is yellowish and not heavily tarnished.