There is a wide range of materials that can be machined by CNC machines, and metals are no exception; CNC machines are a great option for making 3D metal parts due to their high precision and accuracy.
Metals that are suitable for machining have specific mechanical properties, such as strength, flexibility, and hardness. Due to the different properties of metals and alloys, there is a wide range of metals and alloys that are easy to machine.
The choice of metal depends on many factors, but as far as cost is concerned, one can generally assume that the more difficult a metal is to process, the more expensive it will be. This is because it takes more time to process. The cost of raw materials can also affect the overall cost of the part.
Aluminum is considered the most cost-effective metal when it comes to CNC machining. This is because it is easy to machine, generally inexpensive, and has an excellent strength-to-weight ratio. This means that aluminum parts are suitable for a wide range of applications and can be produced quickly and inexpensively.
Aluminum 6061 is considered an economical material that is excellent for processing and machining. It is considered an all-purpose material and is therefore versatile. While this grade has good weathering resistance, it is not resistant to chemicals or salt water.
Aluminum grade 7075 has a wide range of useful properties such as ductility, high strength and fatigue resistance. Its high strength makes it an attractive material for the aerospace and automotive industries, but it is one of the more difficult materials for CNC machining. This grade is therefore more suitable for machining less complex parts.
While stainless steel is not as machinable as aluminum, it can still be machined well. Combine this with the relatively low cost of raw materials, stainless steel can be an economically viable metal for your part.
SS304 is the most widely used stainless steel and is used in a variety of household applications such as kitchen utensils and appliances. Due to its good weldability and formability, SS304 is also used for pipes and machinery.
SS303 grade is widely used in shafts, gears and aircraft fittings due to its durability and corrosion resistance. Due to its sulfur content, it is not hardenable by heat treatment.
SS316 grade is incredibly strong and corrosion resistant. It is commonly used for specialty applications such as medical implants and in the aerospace industry.
Other types of steel and steel alloys may be a more economical option compared to stainless steel. While other steels are not as corrosion resistant as stainless steel, they can have similar properties.
Steel alloy 4140 is a low-alloy steel that contains manganese, chromium and molybdenum. It has excellent properties of high fatigue strength, toughness and impact resistance, making it an attractive alloy for many applications and industries. Compared to stainless steel, this alloy is a more economical choice.
Titanium is the most expensive metal for CNC machining. This is due in part to its low thermal conductivity and high strength, which make it difficult to machine. The combination with the high cost of raw materials makes titanium so expensive to machine.
Companies offer grade 5 Ti6AI4V titanium, which has an excellent strength-to-weight ratio as well as chemical and temperature resistance. These properties make titanium suitable for specialized applications in extreme operating environments, making it widely used in medical, aerospace and high-end automotive applications.
Brass is an alloyed metal composed of copper and zinc. As a result, it is easy to machine, but the slightly higher cost of the raw material increases the overall cost of machining. However, brass retains its value as scrap.
Properties of brass include: medium hardness and high tensile strength – making it a good choice for electrical, medical and automotive applications.