Brass holds an important place in modern manufacturing. It has unique properties. To make brass products efficiently, CNC machining is key. It leads the industry’s trend. Brass has excellent conductivity. It resists corrosion and is strong. These qualities have made it ideal for CNC machining. The next part of this article will focus on the definition, types, properties, and advantages of brass. It will end with a discussion of CNC machining brass tips. This will give you a primer on choosing CNC machining brass. Now let’s start together!
Table of Contents
Definition and types of brass
Brass is an alloy of copper and zinc, usually containing 65-90% copper and 10-35% zinc. It may also contain other metallic elements such as silicon, iron, lead, or magnesium. This alloy is widely used to make many parts and decorations. This is because it has a beautiful golden shine, is easy to machine, and resists corrosion.
Brass is mainly divided into common brass and special brass. This division is based on its different chemical compositions and properties. Brass is made of copper and zinc. It is called ordinary brass if it is just those two metals. Ordinary brass has 20-40% zinc. It has good plasticity and strength. It is often used to make pipes, plates, and wires.
If it has more than two elements, it is called special brass. Special brass refers to improving the performance of ordinary brass, usually in ordinary brass added Sn, Pb, Mn, Ni, Ti, Al Fe, and other elements are to form a multi-alloy, to improve some of its properties. For example, lead brass has good cutting and wear resistance. It is commonly used to make gear parts. Tin brass has high corrosion resistance and strength. It is suitable for ship parts and so on.
What Properties Of Brass Make It Suitable For CNC Machining?
Excellent Machining Performance
Brass is one of the easiest metals for CNC machining. First of all, brass has good plasticity. This lets it deform a lot without breaking when external forces are applied. It can be easily molded into many shapes and structures. This can be done by rolling, stretching, or extruding.
Secondly, the cutting performance of brass is excellent. Brass has a low hardness and good ductility, making it excellent in cutting, drilling, turning, and milling processes. In turning, milling, and other machining, the chips are easy to break, the tool wear is less, and a high surface finish and precision can be obtained. Brass has low cutting resistance. The heat it makes during processing is less. It is hard to damage the tool. This prolongs the tool’s life.
Furthermore, brass has excellent thermal processing performance. At high temperatures, brass is more fluid. This is useful for casting, forging, and other hot working processes. It can make large and complex parts.
In addition, the degree of cold work hardening of brass is relatively low. After cold working, its hardness and strength increase little. The following annealing is also easier. It can restore its good plasticity and toughness. This is good for further processing and molding.
Brass has great machining properties. So, it has become important in CNC machining. It is widely used in industries such as electronics, automotive, aerospace, construction, and decoration.
Excellent Corrosion Resistance
The corrosion resistance of brass is due to its alloy composition. Brass is a Cu-Zn alloy with Zn as the main alloying element. Due to its compositional properties, brass corrodes very slowly in the atmosphere, and brass can form a protective oxide film when exposed to air, which prevents further oxidation and corrosion. The corrosion rate in pure fresh water is also small, showing relatively good basic corrosion resistance.
Brass resists corrosion well in seawater and similar places with chloride ions. This is unlike pure copper. In particular, the addition of a small amount of tin and aluminum special brass, can effectively resist the corrosion of chlorine ions in seawater. This makes brass widely used in shipbuilding. It is also used in marine engineering, underwater equipment, and other fields.
In addition, brass can also show some corrosion resistance in some acid and alkali environments. For example, brass with a bit of arsenic can stay stable in sulfuric and hydrochloric acid. But, brass with added aluminum does well in alkaline environments. However, other factors also affect its corrosion resistance. These factors include temperature, humidity, and the composition and structure of brass.
Aesthetic and Functional Advantages
Brass has unique aesthetic and functional advantages that make it highly desirable in many areas.
In terms of aesthetics, brass has a warm and charming golden yellow shine. Over time, a layer of oxidized film forms on its surface. This adds a rustic and elegant texture. This unique change in color and texture gives brass an age-old flavor, making it a favorite in Art Deco and vintage style design. Brass is easy to treat with various surface techniques, like polishing, plating, and coating. It can make many surface effects, such as mirrors, matte, and antique bronze. This adds to the metal’s aesthetic flexibility. So, whether it is used to make exquisite jewelry, ornate lamps, or artistic furniture accessories, brass can add a noble and luxurious feel to the works.
In terms of functionality, brass has good electrical and thermal conductivity. This makes it widely used in electronic and electrical fields, such as manufacturing connectors and plugs. At the same time, brass is moderately strong and hard. It has good resistance to abrasion and corrosion. It can work well in many tough environments. In addition, brass is easy to process and molding can be casting, forging, stamping, and other processes, manufacturing complex shapes, and high precision requirements of parts and products.
Electrical and Thermal Conductivity
Brass is a good conductor of electricity and heat. This property is mainly due to its copper content. These metal alloys are good conductors of electricity and heat. EDM is therefore the best CNC process for machining them. This machining process reduces the cost and processing time of manufacturing brass parts. It also makes it easier to manufacture electrical equipment with brass parts (e.g. heat sinks).
Ductility
Ductility is the ease with which a metal can be shaped into different forms by hand. Brass is very flexible and highly malleable. Because this alloy is easy to shape, it is ideal for CNC machining. Businesses can use CNC machining to create unique brass parts.
One of the main reasons brass is easy to shape is because it contains copper. Therefore, brass metal with a high copper content is easier to shape than brass metal with a low copper content.
Strength and Hardness
People don’t usually consider the strength and hardness of brass. It is easy to work because of its low coefficient of friction. However, this copper alloy is very strong and durable, although not as strong as steel. For best results, carbide cutters should be used during processing. The strength of the brass alloy comes from the aluminum alloy component that makes it up. The aluminum alloy component can form a hard aluminum oxide layer on the surface of the alloy.
Diversity of Brass Applications
Automobile and Aerospace
- Automotive Parts: Brass is used in the automotive industry to manufacture radiators, cooling system parts, and electrical connectors. Its heat and corrosion resistance ensures the long life and reliability of automotive parts.
- Aerospace: Brass is used in the aerospace industry to manufacture high-precision instruments, connectors, and fuel system components. Its great mechanical properties and fatigue resistance meet the strict needs of aerospace.
Industrial and Mechanical
- Mechanical Parts: Brass is widely used in the manufacture of mechanical parts such as gears, bearings, valves, and pumps due to its high strength, wear resistance, and good machinability. These parts need to work in high-load and high-wear environments.
- Ship and Marine Engineering: The corrosion resistance of brass is particularly suitable for marine environments. It is widely used in making ship fittings, propellers, and marine valves. It is also used in marine engineering equipment.
Electronics and Electricity
- Electrical Connectors: Brass is widely used in the manufacture of electrical connectors, connectors, switches and terminals due to its excellent conductivity. Brass has high electrical conductivity and strength. This makes sure that electrical connections using it are reliable and durable.
- Radiators and Heat Exchangers: The excellent thermal conductivity of brass makes it an ideal material for the manufacture of radiators and heat exchangers. These components are commonly used in electronic equipment, air conditioning, and refrigeration equipment.
Architecture and Decoration
- Architectural Decoration: Brass is commonly used to make architectural decorative parts such as door handles, railings, lamps and door frames. Its unique luster and elegant appearance add noble and classical beauty to buildings.
- Sculpture and Artwork: The good plasticity and surface finish of brass make it an ideal material for sculpture and artwork. Artists and craftsmen can use brass. They use it to create fine sculptures and decorations.
Grades of Brass Commonly Used in CNC Machining
Commonly used brasses are categorized into the following grades based on the copper and zinc content of the brass:
C464-Navy Brass
This brass contains about 60% copper, 39% zinc, and 1% tin. The addition of tin improves its corrosion resistance and makes it particularly suitable for marine environments. Its high strength and good fatigue resistance make it excellent in harsh environments. It is mainly used in the manufacture of ship fittings, propellers, and other parts that require high corrosion resistance.
C230-Red Brass
It contains about 85% copper and 15% zinc. It has high electrical conductivity and excellent corrosion resistance for electrical and electronic applications. Its beautiful reddish-yellow color makes it popular for decorative applications as well. The main applications are in the manufacture of electrical contacts, connectors, and musical instruments.
C260-Cartridge Brass
Contains about 20% zinc and was historically used for ammunition cartridges, hence the common name cartridge brass. It has good thermal conductivity, corrosion resistance, and tensile strength. It is used to make parts like electrical outlets and pressure systems.
C360-Free Cutting Brass
Containing about 60% copper, 36% zinc, and 3% lead, C360 brass has excellent machinability and is known as “free-cutting brass”. Its lead content improves cutting performance, making it ideal for CNC machining. It is widely used for precision parts such as bolts, bearings, gears, and electronic connectors.
Surface Treatment of CNC Machined Brass Parts
Brass with a surface treatment usually has a natural golden surface, which can be used as a natural finish. If your brass parts require it, you may want to add a surface treatment to CNC machined brass parts. The following are some of the different surface treatments that can be used on CNC machined brass.
Polishing
This is a surface finishing process that improves the appearance of the brass by removing debris from the surface of the alloy. In addition, honing creates a cross-hatch pattern on the surface of the brass part. This can make it look more attractive. Polishing also ensures the precision of machined brass parts by checking the dimensions, shape, and straightness.
As Machined
This means using machined brass without surface finishing. When using this type of brass, practicality is more important than appearance. However, surface finishing usually adds an extra layer of protection. Therefore, using machined metal may shorten its lifespan as it is more prone to damage.
Powder Coating
To achieve this surface effect, we spray the outside of the hand-finished brass parts with free-flowing dry powder. Powder coating is a very useful surface effect. It makes the brass more corrosion-resistant and therefore lasts longer.
Electroplating
This surface treatment makes the brass look smoother and shinier than other surface treatments. Electrolysis is used to attach the molecules of another metal to the brass surface. Aluminum, stainless steel, and other metals can also be used for this purpose. In most cases, chrome, copper, silver, or gold are electroplated onto the brass.
Successful Brass CNC Machining Tips
Brass is popular in CNC machining for its good machinability and excellent performance. Yonglihao Machinery has many years of experience in brass CNC machining, here are some brass CNC machining tips we share:
Choosing the Right Brass Material
Choosing the right grade of brass is crucial. Free-cutting brass (e.g. C360) is ideal for CNC machining, as its lead content improves cutting performance and reduces tool wear and machining difficulty.
Optimizing Cutting Parameters
The setting of cutting parameters directly affects machining quality and efficiency. When selecting cutting parameters, it is necessary to consider factors such as tool type, depth of cut, cutting speed, feed, and so on. For brass, it is softer. So, you can increase the cutting speed and feed. But, be careful. Too much cutting can damage the tool or part.
Use the Appropriate Tool
The choice of tool is crucial for brass CNC machining. According to the shape, size, and accuracy requirements of the machined part, select the appropriate tool material and geometry. For brass, it’s best to use carbide tools. They are hard and wear-resistant. They are good for cutting soft metals.
Formulate Reasonable Machining Sequence
When planning the machining sequence, do the rough machining first to remove most of the leftover material. Then, do the finish machining to ensure precision and surface quality.
Optimize the CNC Program
Write optimized CNC programs to reduce tool idle travel and machining time. Use efficient machining paths and strategies. For example, use spiral feed and isometric cutting. These strategies optimize the machining process.
Select Suitable Coolant
Select a suitable coolant to reduce cutting temperature, minimize tool wear, and improve machining quality.
Conclusion
Brass is a common cutting material in CNC machining. It’s chosen for its excellent machinability, corrosion resistance, and aesthetic and functional benefits. It’s also chosen for its wide range of uses. If you want to know more about this, you can contact Yonglihao Machinery, we will give you a more detailed answer. If you have brass CNC machining projects and needs, please also contact us. We will provide you with better CNC machining services and high-quality products.
FAQ
Why is brass favored in CNC machining?
Brass is popular in CNC machining. This is due to its good machinability, physical properties, and appearance.
Brass is popular in CNC machining. This is due to its good machinability, physical properties, and appearance.
Brass is used in many industries. These include automotive and aerospace, industrial and mechanical, and electronic and electrical. It’s also used in architecture and decoration.
What types of brass are best suited for CNC machining?
C360 free-cutting brass, C464 navy brass and C230 red brass are common choices.
How does the machinability of brass compare to other metals?
Brass is easier to machine than many other metals, reducing production time and tool wear.
What surface finish options are available for brass parts?
Common surface finishes include polished, brushed, plated, chemically plated, and sandblasted.