Posted On: August 7, 2020
Precision CNC machining is a process of manufacturing dimensionally accurate components. This is usually performed for manufacturing intricate components in the aerospace, automobile, modern electronics industries, etc. In order to achieve precision in CNC machining, along with advanced technologies and skilled workmanship, the selection of correct material is very important. Generally, the material for precision CNC machining requires properties like dimensional stability, machinability, and workability, corrosion resistance, and impact resistance, etc. There are several materials that meet these criteria, however, not all may be suitable for your application. To choose the right material it is important to know their properties and uses. This post presents a list of raw materials that possess these properties and are suitable for precision CNC machining.
One of the key reasons for the popularity of CNC machining is its compatibility with various materials. CNC machining can be performed on metals, metal alloys, composites, semiconductors, and engineering plastics. However, precision CNC machining demands a specific selection of raw materials. The following are a few common materials considered for the purpose:
- Stainless Steel:
Stainless Steel (SS) is undoubtedly the most commonly used material for precision CNC manufacturing. The term stainless steel encompasses a wide range of grades such as SS303, SS304, SS316, etc. The difference in all the materials under the range of SS is the number of doping materials added. In SS303, sulfur is added for better machinability and rust-free experience. In SS304, nickel and chromium are added to enhance toughness and reduce magnetic properties. Whereas, SS316 features molybdenum to achieve marine-grade stainless steel. SS316 offers high weldability, machinability, and corrosion resistance. All these aforementioned grades of stainless steel are suited for precision CNC machining.
Steel is one of the metal alloys that are used for precision CNC manufacturing. It offers high dimensional stability and machinability. Different grades of steel are considered for precision CNC machining. They include mild steel, carbon steel, plain carbon steel, and low and high alloy steel. Mild steel offers good ductility where carbon steel offers high strength. Plain carbon steel is preferred for low ductility and high strength applications. Alloy steel can be formed according to requirements by doping with molybdenum, nickel-chromium. Therefore, alloy steel can be used for applications that require properties like corrosion resistance, durability, weldability, etc.
Brass possesses excellent machinability, which helps in achieving expected dimensions to the utmost accuracy. Brass offers accurate tolerance during machining and surface finish post-machining. Different grades of brass are used for different requirements. A few commonly used grades of brass are C35300 and C36000. Brass C35300 assures excellent corrosion and wear resistance. However, C36000 is suitable for parts that demand higher precision. It offers superior machinability, therefore dimensional stability and surface finish can be achieved by using this grade.
- Aluminum and Aluminum Alloys:
Aluminum is a lightweight material. It is non-magnetic in nature, which makes it suitable for CNC machining. It offers low deformation factor, high dimensional stability, and impact resistance. Therefore, aluminum and aluminum alloys sustain accurate dimensions under different conditions like temperature fluctuations, external impact, etc. Like stainless steel, various grades of aluminum have gained popularity. The following are a few popular ones.
- Aluminum 6061:
It the most popular grade of aluminum. It offers excellent mechanical properties such as high strength, corrosion resistance, toughness, and weldability.
- Aluminum 7075:
It offers great fatigue resistance and therefore is used for intense industrial applications. Aircraft wings and fuse glasses are made of this material.
- Aluminum 2024:
It offers high thermal resistance, shock, and fatigue endurance, therefore it is used for military and aerospace applications.
- Aluminum 5052:
It offers great chemical and corrosion resistance. It is also non-heat treatable, therefore is used in marine applications.
- Aluminum 6063:
It is a heat treatable alloy that allows high weldability, and durability. It can be used for making complex components.
Titanium is highly immune to heat and oxidization. It also is very compatible with bio-factors. Its biocompatibility makes it highly appropriate for mission-critical applications in the medical, chemical, and aviation industries. Although, it is hard to machine, yet with the help of CNC machining, its workability can be enhanced. Commonly used Titanium grades are Titanium 1-4 that offer gradually increasing tensile and yield strength. Titanium grade 5 is suitable for temperature resistance whereas Titanium grade 9 is popular for durability that it assures.
Copper being a non-ferrous material, it is immune to corrosion. It offers electrical conductivity and durability, therefore it is suitable for precisely manufactured electronic components. Copper alloys such as brass, bronzes, nickel silver, copper-nickel-alloy, etc are used for various applications. Since the list of raw materials for precision CNC manufacturing is detailed, it is important to understand that the material selection needs to be done efficiently. If you are confused about the right selection then you must approach experts like BDE, Inc. The company has been providing precision CNC machining services for several years now. They have been working with most materials covered in this post.