CNC machining is a modern manufacturing process that turns raw materials into precise products. It uses computer-controlled machines that cut and shape the materials. Those machines can work with various materials, but choosing the right one is key. I have explored and prepared a list of the top 10 CNC machining materials.
All of these materials come with unique properties. Some can handle heat, and some are lightweight and easy to shape. However, the wrong material not only leads to tool wear but also affects the quality of the products. Thus, to help you make a wiser choice, let’s discuss the top 10 CNC machining materials with their applications.
Top 10 CNC Machining Materials with Applications
As I said above, a CNC machine can handle a variety of products. However, the final product is only as good as the material used to make it. So, choosing the most reliable material is crucial in CNC machining. I have explored the top 10 materials, simplifying this process. So, let’s dive in and analyze those materials with their specifications.
1- Aluminum
Aluminum is one of the popular choices for CNC machining. WHY? The first reason is that it is lightweight. It has a density of 2.7g/cm³, which is much lower than other materials. Moreover, the atoms in its structure are highly spaced, making it lightweight yet strong. That’s why CNC machines can easily cut, drill, and shape it, which reduces the machining time.
Applications: Aluminum is used in the aerospace industry due to its lightweight. For example, it makes aircraft wings and engines. The automotive industry also uses this metal to make wheels, blocks, and brackets. Lastly, it is also used in making phone bodies, laptop casings, and heat sinks.
2- Stainless Steel
Stainless steel is another top choice for CNC machining. It is known for its durability and corrosion resistance. The higher chromium content in stainless steel forms an oxide layer. This layer protects the surface from further corrosion so that it can last long, even in harsh environments. Moreover, stainless steel can handle heavy loads and stress without breaking due to its higher tensile strength.
Applications: Stainless steel is used in making medical equipment due to its non-porous surface. This surface prevents contamination and bacterial attacks. In the automotive industry, it makes exhaust systems and valves for vehicles. Moreover, high corrosion resistance makes it ideal for marine parts, e.g., ship docks.
3- Mild Steel (Carbon Steel)
Mild steel is a commonly used material for CNC machining. It is a special type of steel that contains 0.3% carbon, which makes it strong but not too hard. This means that mild steel is easy to cut, drill, and weld with CNC machines without the risk of breaking. Moreover, it offers higher flexibility, which makes it versatile for making complex shapes. Lastly, unlike stainless steel, it is affordable, which lowers overall costs.
Applications: Mild steel is used to make machine parts due to its higher strength. The automotive industry uses it in vehicle brackets and frames. Moreover, furniture frames such as tables and racks can be made of it. Carbon steel is handy for making gears, shafts, jigs, and fixtures in industrial equipment.
4- Brass
Brass is an alloy of copper and zinc. It offers an excellent weight-to-strength ratio and is considered a top choice for CNC machining. Other materials often produce more friction during the machining process. However, it produces less friction and heat, reducing tool wear. Moreover, brass is known for its rust-proof and shiny golden appearance. This makes it perfect for creating complex decorative items using CNC machines.
Applications: Due to its corrosion resistance, brass is used in plumbing systems. Moreover, brass has high electrical conductivity. That’s why you can use it to make switches, connectors, and terminals. Lastly, its magnetic properties make it ideal for aerospace and defence systems.
5- Copper
Copper is a reddish-orange metal known for its easy fabrication due to its higher ductility. That’s why you can use it to make complex shapes using CNC machining. Moreover, no other metal is as good a conductor of heat and electricity as copper. It can absorb and transfer heat quickly, making it perfect for making thermal parts. Moreover, copper is naturally corrosion-resistant due to the patina layer. So, it can handle different harsh, moist, and salty environments.
Applications: Excellent electrical conductivity makes copper ideal for making circuits and connectors. Moreover, due to its natural antimicrobial properties, it is used in medical equipment. It is used in radiators and connectors in the automotive and aerospace industries.
6- Titanium
Titanium is one of the most prominent materials used in CNC machining. Although it is strong like steel, it is very lightweight. That’s why it can be easily fabricated with CNC machines. Moreover, titanium is also known for its higher durability. Once you have machined it, the parts will last for several years. Besides, titanium is highly heat resistant. Thus, it can withstand the friction heat during machining and does not melt.
Applications: Titanium has higher biocompatibility. So, it is used in making bone screws, plates, and dental implants. Moreover, it can handle harsh chemicals effectively. That’s why the chemical industry uses it to make valves and containers. Lastly, the marine, military, and automotive industries use titanium in different parts.
7- Plastics
Plastic is the most easy-to-handle and cost-effective material used in CNC machining. It is lightweight and flexible, hence, easy to shape and fabricate. That’s why it is primarily ideal for prototypes and product testing. Moreover, it produces less friction due to its smooth surface, which reduces tool wear. Different types of plastics are used in CNC machining; some of them include:
- ABS (Acrylonitrile Butadiene Styrene): Strong and tough
- POM (Delrin or Acetal): High strength and low fraction
- Nylon: Good dimensional stability
- Polycarbonate (PC): Transparent and strong
- PTFE (Teflon): Heat-resistant and slippery
Applications: Due to their nonmetallic nature, plastics are highly corrosion-resistant. Thus, they are used in automotive and aerospace parts. Moreover, they are also used in surgical tools, braces, and casings in the medical industry. Lastly, plastic is an insulator of electricity. Thus, you can use it for insulation parts and circuit board covers.
8- Tool Steel
Tool steel is a special type of robust and hard steel. It is named “tool steel” because it is mainly used in making different tools, such as dies and molds. I used this material for several reasons in CNC machining. One main reason is its dimensional stability. This means that when machined, it maintains tight tolerances and stays stable. Moreover, high-grade tool steel can resist high temperatures and be shaped easily by heat.
Applications: Tool steel is used to make drill bits, milling cutters, and lathe tools. Due to its tight tolerances, it is also used in making dies and molds for high precision. Industrial machinery parts such as cams and bearings also use this material.
9- Magnesium
Magnesium is another top material for CNC machining. It is the lightest material, even 30% lighter than aluminum. However, its light weight doesn’t mean it is weak; it has a good strength-to-weight ratio. This means magnesium is light yet strong, offering easy machinability and saving time and cost. Moreover, it has vibration-absorbing properties that ensure accuracy during machining.
Applications: Magnesium’s light weight makes it ideal for the aerospace industry. For example, it makes seat frames and other lightweight structures. Moreover, it is used in cameras, phones, and laptop casings in electronics. Further, medical devices use magnesium in frames and supports.
10- Zinc
Zinc is an all-rounder in CNC machining when you need precision and ease. Although it is not as famous as aluminum and steel, it can still be used for small, detailed parts. Zinc is lightweight, soft, and easy to cut and shape, reducing time and tool wear. Moreover, machined zinc offers a shiny and delicate look, ideal for decorative items. Lastly, it maintains shape and attains tight tolerance so that you can machine it for complex geometry parts.
Applications: Zinc is used in automotive parts to make carburetors, handles, and brackets. It is also used in electronic housings to make connectors and chargers. Moreover, zinc is used in valves and fittings to control water flow. Due to its shiny look, it is also used in art and decoration, such as craft items, sculptures, and customer badges.
Key Considerations While Choosing the CNC Machining Material
From metal to plastic, each material behaves differently under the CNC machine. If you pick the wrong material, you will end up with unwanted results, such as tool wear. Thus, before you make a final decision, let’s look at some considerations you must consider.
- Strength and Durability: First, understand the strength of each material. If you want a part that can handle high pressure, you should never compromise on strength. Go for titanium, stainless steel, and carbon steel for strength.
- Weight: Evaluate the weight consideration of your project. For example, if your project demands higher strength but low weight, you should use aluminum. However, if lightweight is not your concern, you can choose brass and stainless steel.
- Machinability: This refers to how easily you can fabricate the materials. Some materials, such as plastic, aluminum, and brass, are easy to machine. However, some materials, e.g., titanium and Inconel, are more challenging and cause tool wear. So, you should choose more easy-to-machine material to save time and money.
- Availability and Lead Time: Some materials are readily available. You can find those materials when you need them. However, some take time and effort to source. So, if you are working to a tight deadline, you should prefer readily available materials.
- Cost and Affordability: Different materials come at different prices. So, before choosing any material, keep your budget in mind. For example, aluminum, plastic, and mild steel are cost-effective options. However, titanium, stainless steel, and super alloys are expensive.
Conclusion
CNC machining opens endless possibilities in product manufacturing. However, the quality of those products heavily relies on the material you choose for CNC machining. The wrong material can ruin the time and waste money. I have discussed the top 10 CNC machining materials and their applications.
Each material has unique properties, from lightweight aluminum and magnesium to heavy brass and copper. Moreover, all these materials perform distinct duties in various industries. So, before you choose the final material for machining, consider some factors. For instance, you should evaluate your project needs, material prices, strength, and weight.