JCL Precision Part Co.,Ltd.

Everything You Need to Know About Brass

What is brass?

If we try to define Brass, then it’s a material that consists mainly of copper and zinc. It is characterized by its yellow color, which resembles gold. Brass composition can differ due to the amount of copper and zinc in the alloy.


What is brass composition?

The brass composition knowledge requires an understanding of alloys that are made by the combination of copper and zinc. Alloys are materials that are created by mixing two or more elements, where the compound shows characteristics that are different from the individual elements.


Copper and zinc could be combined in different proportions to produce various alloys. They are known for their special features and each of them is suitable for a particular kind of application. The most famous alloy formed by combining copper and zinc is brass.


Different compositions of copper and zinc alloy

Brass is an alloy of metals made of copper and zinc in differing proportions. Copper and zinc are melted in definite proportions to form it. The brass composition is explained based on copper and zinc percentages.


Five kinds of brass are characterized by their copper and zinc content. The amount of copper and zinc in the brass alloy determines which type of composition is utilized here. The five types are;

1. Alpha brass

This grade is made of 65% copper and 35% zinc alloy. It is well-known for being able to be cold-worked and is commonly used to make musical instruments, decorative items, and plumbing fixtures.

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Alpha Brass Gas Pipe Fittings

2. Alpha-beta brass

Alpha-beta brass is a type of alloy that consists of approximately 55% copper and 45% zinc. This brass composition represents a combination of strength, corrosion resistance, and ease of machining. It can be found in connectors, cartridge cases, and plumbing parts.

3. Beta brass

This Brass alloy consists of 45% copper and 55% zinc. Beta bronze is highly plastic and able to be shaped 

easily. This material has found its application in the making of jewelry, decorative items, and watch parts.

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Beta Brass Old Antique 

4. Cartridge brass

It is a brass has copper and zinc composition with exact percentages of 70 and 30 respectively. The primary advantage of drawn brass is its inherent higher formability means it's easy to process though different forming processes. Extensive usage is found in the production of ammunition, plumbing fixtures, and musical instruments.

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Cartridge brass bullet shell

5. High brass

The high brass is created from a copper-zinc alloy with 65% and 35% respectively. The alloy is mainly intended to be used on corrosion lasting situations such as fittings, electric connections and fasteners.

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High Brass Straight Connectors



Special Alloys of Brass

As brass is man made materials, there is nothing that brass cannot be engineered to achieve. There are four special alloys of brass developed by engineers to achieve some very specific outcomes that no other material can deliver.

Muntz Metal

This specific alloy of copper and zinc that is technically known as the brass alloy 280 is a special alloy of brass. It was developed by making a mixture of 60% copper, 40% zinc, and traces of iron. This mixture makes a brass with very similar properties of copper as thus it can be used as an alternative of copper in boats hull. This Muntz metal helps prevent the growth of marine organisms on boat hulls.

The Machining Brass

This special alloy of brass is made with 60% copper with an exact thirty five percent of zinc and about 3.7 percent of lead and some traces of other elements like iron. This makes this brass alloy very easy to manufacture and it's easiest to machine as compared to all other brass alloys. Technical name of this material is Alloy C360 and it is used in manufacturing products like brass gears and bushes. 

The Architectural Bronze

This special alloy of brass is made with 59% copper with an exact thirty seven percent of zinc and about 3.5 percent of lead and some traces of other elements like iron. This makes this brass alloy very good for machining and forming. Technical name of this material is Alloy 385 and it is used in structural and architectural applications.

The Naval Brass

This special alloy of brass is made with fifty nine percent copper with an exact forty  percent of zinc and about one percent tin. This makes this brass alloy exceptionally good at corrosion resistance. Technical name of this material is Alloy 464 and it is used in all types of marine applications.


Physical Properties of Brass Material

In brass, there are physical characteristics that make it superior among all materials. These numerous applications throughout various sectors are thanks to high brass density, corrosion resistance, thermal expansion, thermal conductivity, and electrical conductivity. 


By comparing melting and boiling points it can be inferred that brass is a mixture of copper and zinc which are its main components. It is vital to be aware of the physical properties of this metal since it is the ground for determining how it is applied.


1. Density: In terms of brass material, density is the factor that largely depends on its composition. The density of brass lies in the range of 8.4 to 8.7 g/cm3.

2. Corrosion Resistance: The fact that brasses contain the highest corrosion resistance and ages slower, makes them an ideal option as they exist in a larger application variety. The alloy of zinc and copper raises the product durability in terms of corrosion resistance and rusting.

3. Thermal Expansion: Brass is a material of medium coefficient of thermal expansion and it can undergo considerable dimensional changes due to temperature fluctuations. Brass has dimensionality as one of its characteristic properties that allows it being used in the production of huge high-accuracy parts or in the machining processes.

4. Thermal Conductivity: It can be said that brass is an excellent conductor of heat and the heat transmits from brass to materials. This is the factor that makes it valuable enough since it is used in radiators and heat exchangers as well as in thermal conductivity and heat dissipation.
5. Electrical Conductivity: Likewise, brass material is another excellent electrical conductor. It can be used as an electric conductor which makes it suitable for electrical and electronic components like terminals and connectors.

6. Boiling Point: Because brass material is an alloy and doesn’t have a particular boiling point, the boiling point of such material does not apply. It majorly consists of zinc and copper whose boiling points are 907°C and 2567°C respectively. As an Alloy,  the boiling point will vary with the amount of zinc and copper mixture.

7. Melting Point: Usually, brass melts in the range of 900 to 940°C. But being an alloy it can alter its melting point by changing its composition with additional elements.


Mechanical Properties of Brass Metal

Among all the metals, brass metal proves to be of high value not only because of its aesthetic look but also for its wide range of mechanical properties which are admirable for many industrial uses. These properties can be varied with all the brass alloys because of the specific components which can be selected and improved by changing the ratio of copper to zinc. 


Yield Strength: The yield strength of brass metal is the ultimate stress the material can endure without permanently deforming. While you are engineering components that experience high loads or stress, careful consideration is essential.

Ultimate Tensile Strength: The upper limit of stress that this metal can withstand before fracturing is termed the ultimate tensile strength of brass. The characteristic ultimate tensile strength of the brass alloy can range between 450 MPa and 600 MPa.  It is an important one, as far as metal strength is concerned since it quantifies the metal's resistance to tensile forces.

Hardness: As for the hardness of brass, it is dependent on its composition. Resistance to wear or indentation is known as the "hardness" of the material. brass metal provides some strength while also being malleable and has an average hardness value of 60 on the Brinell scale. It is an important factor to be considered when investigating the ability of the material to break.

Toughness: It is described as the quality of a brass metal to not be broken by any sort of stress as its toughness. It measures to what extent something can withstand shock and impact. The toughness is mostly related to the operating temperature of brass material. 

The maximum value of toughness of brass metal is 20,0 to 2100 Joule at 1110 degrees Celsius temperature and then the minimum impact toughness is 1700 to 1800 Joule at 1260 degrees Celsius temperature. Higher strengths associated with increased shock and cracking resistance under dynamic force conditions.

Fatigue strength: Repeated exposure of a material to some kind of cyclic strain without breaking is referred to as fatigue strength. The fatiguing strength of brass metal is on average 200-250 MPa. High fatigue strength brass alloys often get chosen for purposes like gearbox wear pads or hair-spring vibratory applications with cyclic loading.

Elasticity: Elasticity refers to the property of materials to deform under tension and recover to the original shape after the stress is removed. The ultimate tensile strength of brass metal is about 350–400 MPa in ideal circumstances. Due to its good adaptability, brass can flex and accommodate shocks without always undergoing permanent deformation.

Plasticity: The term. "plasticity" denotes the material's capability to be permanently deformed without being broken. The plasticity of brass is expressed by the presence of zinc in the alloy composition. The more zinc added there would lower the plasticity. Thus, the high brass with 45% zinc has the least plasticity among others. Because of their big plasticity brass alloys are relatively easily bent, formed, or machined into the desired shape.

Chemical Properties of Brass Alloy

It is the largest possibility that brass alloy has many beneficial chemical characteristics. Brass texture is soft, has non-toxic formulation, and non-combustible nature broadens its area of application from industrial components to decorative products. 


The brass alloy is a tough material that can endure hard conditions due to its low reactivity and resistance to corrosion. For the sake of health, all necessary precautions should be taken whenever brass alloys are to be processed by corrosive or acidic materials. 


Brass Texture: The shiny and bright surface of the brass alloy makes it stand out among other metals. Maybe it would have a polished surface with a high-gloss finish to make it look refined. Brass, a combination of copper, zinc as well as many other elements has a smooth texture. It can be easily processed and molded into complex shapes.

Toxicity: Generally, the brass alloy is claimed as non-toxic. This material produces no risky compounds while being utilized in everyday conditions. It is essential to notice that brass alloys might give off copper and zinc ions in the presence of some basic or acidic substances. These ions can pose a danger if they are ingested or inhaled in excessive amounts.

Flammability: Since it is not flammable brass alloy does not easily catch on fire and spread combustion. Due to that property, it is an ideal choice of material for many applications which involve fire resistance such as decorative items and electrical fittings.

Reactivity: In normal situations, brass alloy is not easily reactive with most chemicals because of its low reactivity. It does not become boring quickly and it is corrosion-resistant. As a result of this, brass can be used where it gets in touch with chemicals or moisture.

Oxidation: Because of oxidation, the brass alloy may eventually develop a greenish patina on its surface. On exposure to air, the oxygen combines with copper present in the alloy, thus, forming a patina that acts as a natural protection layer. Some of the people who prefer the patina think it is visually appealing, while those who would rather have a brass alloy that still shines like new, polish it.

Solubility: Brass alloys are poorly soluble in water and most organic solvents. This feature makes the alloy not disintegrate in liquid systems and remains stable. On the other hand, some acids like the sulfuric or the hydrochloric acids will dissolve the brass alloy which is helpful in some cases of corrosion.


What are some advantages of using brass?

There are several advantages to using brass alloys: There are several advantages to using brass alloys:

1. Rust Resistance: Brass has great corrosion resistance ability therefore it can be used in marine conditions or all cases involving exposure to water.

2. Aesthetic Appeal: The brass alloys have a beautiful golden hue that makes them quite suitable for decorative uses, such as the making of jewelry, musical instruments, and interior décor items.

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copper jewelry

3. Excellent Machinability: Brass is quite easy to turn, drill, and cut because of its advantageous machinability. Considering this property, it is often a preferred material for the manufacture of sophisticated designs or intricate components.

4. Low Friction: A low friction coefficient of brass makes it particularly suitable for components such as valves, gears, and bearings that require low wear and high operational efficiency.

5. Thermal Conductivity: Brass has a good thermal conductivity and therefore it is a suitable material for applications where heat must be transferred. It can often be found in radiators, heat exchangers, and plumbing devices.

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What are some limitations of brass material?

Despite its advantages, brass has a few limitations that need to be considered: Despite its advantages, brass has a few limitations that need to be considered:

1. Lower Strength: Brass is relatively weaker than some other metals, such as steel or titanium. Therefore, this might not apply to structures in which a high degree of structural integrity or load-bearing capacity is important.

2. Susceptibility to Dezincification: At times, due to certain circumstances, the brass alloy may undergo dezincification which refers to the removal of some zinc but leaving some zinc behind which results in deterioration of the material. This eliminates the utilization of such chemicals and high-temperature conditions.


What are some brass metal uses?

Applications of Brass Metal

1. Plumbing and Piping Systems: Brass alloys are commonly used in making plumbing fittings, valves, and connections due to their high resistance to corrosion and the fact that they are easy to machine.

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2. Musical Instruments: A vast variety of musical instruments, such as saxophones, trumpets, trombones, and other percussion instruments are made of brass alloys. Brass is a great material for different purposes due to its good acoustics and aesthetic appeal.

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3. Electrical Connectors and Terminals: Due to their high electrical conductivity brass alloys can be used not only for every type of electronic equipment but they can also be used as electrical contacts, connectors, and terminals.

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4. Decorative Applications: Brass is a material for jewelry, sculptures, architectural elements, and decorative hardware because of its appearance and usefulness.

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Manufacturing of Brass Parts

Brass being a very useful metal is subjected to several manufacturing and sheet metal fabrication processes to make brass parts. 

Machining of Brass

As brass is not much hard and wears a resistance material, its machining is very easy. Machining brass is much like machining aluminum or copper material. As brass is soft material and not much force is needed for machining, so achieving a quality surface finish is very easy. Brass machining is a very cost effective process.

Forming of Brass

Brass being a very ductile machine with high plasticity it’s very easy to perform all types of forming process on brass. Processes like brass sheet metal cutting, brass sheet metal bending, and brass metal stamping can be performed effortlessly. The surface finish obtained during forming of brass parts is very good and mostly does not require any post process.

Welding of Brass

As copper is the base and most part of the brass materials. So brass has low melting and boiling point as compared to other materials like steel. Due to this, it's very difficult to weld brass using any of the traditional welding techniques like arc welding, gas welding, TIG welding, MIG welding and sheet metal welding. Any attempt of welding brass using traditional techniques will simply result in melting of brass metal from the spot of welding attempted.

Brazing of Brass

Brazing is an alternative of the welding joining process recommended for the brass materials. As brass is a soft material with low melting point. The process involves joining two or more brass parts together by filling the joint with a molten material that solidifies quickly and permanently joins the brass parts. 

Surface Finish of Brass

Brass supports all types of surface finish process to enable custom surface finish for brass parts. Processes like powder coating, electroplating, polishing and anodizing are some of the most common processes that are done on brass. 


Are brass alloys a good material to use

Brass alloy applicability is dependent on the particular conditions of the application. Brass has advantages for many industries as it resists corrosion, is easily machined to desired shapes, and possesses a decorative look. 

However, it has some shortcomings in strength and dezincification. Additionally, for brass alloys to be the right choice, designers and engineers must thoroughly consider the project requirements.

Summary

All in all, brass is a metal alloy with the color of gold and multiple purposes. It is mainly built from copper and zinc. 

Due to its strong, flexible and machinable physical properties, it can be used in a widest range of applications. While it can get discolored after a while, it is chemically resistant to corrosion in most environments. 

Different sorts of brass alloys provide the needs of various industries with a range of hardness, color, and corrosion resistance. 

Thanks to its superior thermal and electrical conducting properties and other physicochemical characteristics, it is perfect for use in plumbing and electrical engineering.


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