What Is Aerospace CNC Machining?
Aerospace CNC machining is a subtractive manufacturing technique that involves creating and maintaining aircraft and space shuttle components with computer numerically controlled tools. This automated manufacturing process uses cutting tools controlled by pre-programmed code and software.
The aerospace industry has high demand for parts made with high-quality materials and has zero margin for error. These aircraft parts often range from hinges, clamps, bushings, and custom machining of aircraft components.
Aerospace manufacturing uses high-quality CNC machining materials to ensure their optimal performance, preventing danger. As a result, Kovar and titanium are commonly used metals in various aerospace machining applications. Examples of other materials include stainless steel, bronze, copper, aluminum alloys, and some plastics.
Common Materials Used in Aerospace CNC Machining
Although not all aircraft and space shuttles’ components are created using CNC machining, many are best produced with CNC machines. However, this section discusses the materials used in CNC machining aerospace parts:
Lightweight Metals
The strength and weight of materials are two factors that determine the ideal CNC machining materials used by aerospace companies. Even though strong, metals like steel are not suitable for aircraft components because steel is weighty.
As a result, the aerospace industry considers strong and lightweight metals like aluminum and titanium alloys as they are highly suitable for aerospace part production. For example, titanium is 50% lighter and 30% stronger than steel. It also exhibits an excellent strength-to-weight ratio and resists corrosion.
Thus, titanium CNC machining is the right option for critical components for commercial and military aircraft like Boeing B787 and Airbus A380. It is also ideal for different parts of helicopters like UH-60 Black Hawk, F-22, and F/A-18. Titanium and its alloys are the perfect materials for making various components for jet engines and airframes.
On the other hand, aluminum has high tensile strength and is more lightweight than titanium. Although aluminum is half as strong as titanium, it is cost-effective and highly machinable.
Therefore, it is ideal for an extensive range of aircraft components. The aluminum 7075 has excellent fatigue stress, making it suitable for aircraft fuselage, filter bodies, wings, and more.
High-Performance Plastics
Most interior components of an aircraft are polymer-based materials, even though the aircraft’s functional structures have more metal components. These plastics are aerospace-grade, usually strong, lightweight, and exhibit excellent vibration resistance.
Additionally, their vibration resistance a well-suited for making parts like bearings, cabin interiors, back-lit instrument panels, ventilation ducts, valve components, etc. Engineers use CNC machining processes to make lightweight and strong plastic parts with complex designs for the aerospace industry.
PEEK, Ultem, polycarbonate, and other high-performance polymers are the typical materials machinists use for plastic CNC machining of aerospace parts. CNC machines offer the high precision required for polymer-based aerospace applications.
Achieving Precision and Tight Tolerances in Aerospace CNC Machining
Precision CNC machining is pivotal in making high-quality aerospace components. The aerospace sector has strict safety controls and high production standards for CNC machining aerospace parts. These parts require the tightest and highest tolerances, dimensions, and performance for every component. This precision machining helps to ensure that these aerospace parts do not fail in flight.
For instance, the fuselage sections and aircraft landing gear components require incredibly tight tolerances and precision. Therefore, you must consider and add all tiny details with the highest accuracy to ensure proper functionality.
Any slight error or imperfection in machining components for commercial aircraft, cargo planes, or fighter jets can result in a colossal loss. As a result, aerospace machining companies ensured CNC aerospace parts meet standard requirements. Additionally, these companies must provide aircraft as soon as possible to meet market demands.
CNC machine shops like AT Machining can provide aerospace prototypes and precision machined components for the aerospace industry using advanced CNC machining equipment. Efficient CNC machining helps to achieve tolerance levels up to 0.002mm, creating aerospace-grade plastics and metals. Besides, advanced post-processing and inspection systems allow you to bring your aerospace prototypes and components up to the required standards.
Multi-Axis CNC Machines for Aerospace Components
Multi-axis CNC machines are advanced machines that offer high-precision components and help to meet high-performance standards. Most components for the aerospace industry have complex geometries that require advanced approaches and high-end work-holding solutions.
Aerospace manufacturers utilize various multi-axis machining technology to create complex parts with reduced machining time. Milling machines, plasma cutters, high-speed drills, and lathes are examples of standard multi-axis CNC machines commonly used in machining different aerospace parts with superior surface finish.
A standard CNC workstation in the aerospace industry encompasses 3-, 4-, and 5-axis CNC machines and more. These multi-axis CNC machines aid in producing parts with the most complex design requirements. The 5-axis CNC machines are famous for their robust capability to machine complex parts in large volumes. These machines can drill, turn, mill, and manipulate parts along the X, Y, Z, and linear axes with greater precision.
Multi-axis CNC machine is the ideal machining solution for the aerospace industry’s complex design and ultra-precision standards. Any modern, competitive CNC aerospace machining shop will utilize multi-axis CNC machining to produce precise parts that meet the required tolerance and custom design.
Cutting Tools and Strategies for Aerospace Materials
CNC machining of several manufacturing strategies that involves using different cutting tools to remove part of the workpiece to create a desired product. However, the aerospace machining process of choice determines the removal strategies. Below are the standard production processes for machining materials for aerospace parts and cutting tools involved:
CNC Milling
This widely used CNC machining strategy involves cutting material from a workpiece with a tool that rotates and moves along axes. This method offers excellent results and cutting ease depending on the CNC machine’s sophistication. The rotating CNC milling cutters consistently make precise cuts on the fixed workpiece. Other milling tools include fly cutters, face, slab, and hollow mills.
CNC Drilling
CNC drilling is a technique that involves material removal from a workpiece using a rotating cutting tool. This strategy creates a cylindrical hole in a stationary workpiece. This process uses drill bits to make accurate holes to accommodate bolts and screws for fastening or assembling aerospace components.
It is a well-suited strategy for producing aerospace parts that require assembly. Center, ejector, and twist drills are commonly used drilling tools.
CNC Turning
The CNC turning method involves feeding a rotating material to a cutting tool to create a desired design. This process involves using a turning machine or lathe to rotate the workpiece at high RPM (Revolutions per Minute) as the turning tool creates the desired shape from the material.
However, the turning procedure and tools adopted determined the workpiece’s shape. Common examples of turning tools include boring, knurling, parting, and chamfering tools.
Finishing and Coating Aerospace CNC machined Parts
Even though there are several surface finishing options for CNC parts, not all surface finishes are suitable for the purpose. Aerospace manufacturers utilize four major types of surface finishing and coating. These include:
Passivation
Passivation is a widely used finishing technique that enhances aerospace CNC machined parts’ aesthetics, durability, and functionality. Most aerospace parts often contain impurities or micro-roughness after machining operations, which may hinder the part’s performance in the long run. However, you can avoid any complications with passivation. It helps maintain aircraft parts’ chemical resistance and reduces maintenance needs.
Anodizing
Anodizing finish involves submerging aerospace parts in an electrolyte solution, creating an even oxide layer on the component’s surface. For instance, aluminum anodizing provides components that have a surface finish that prevents them from corrosion. Besides, two types of anodized finish are used on aerospace parts: type II and type III.
Type II anodizing creates a thin and decorative layer on a part’s surface. This slim protective layer, however, leaves the product vulnerable to abrasion and corrosion. Conversely, the type III anodizing method provides a hard protective layer on the part’s surface.
Polishing
Polishing is an ideal and straightforward finishing technique for enhancing the surface of CNC aerospace parts. This surface treatment involves using an abrasive to smoothen the rough and coarse surface of the aerospace part till it is smooth and attractive.
Moreover, polishing effectively enhances the durability of aerospace machined parts by reducing the risks of cracking or chipping. However, polishing aerospace parts can take longer and increase CNC machining costs.
Powder Coating
This is another commonly used surface finish for metal aerospace components. Its longevity and functional diversity make it a widely embraced technique for finishing CNC machining aerospace parts. Powder-coated CNC parts resist scratches and do not fade quickly over time. Besides, this finishing option offers aerospace parts manufacturers an extensive range of colors for improved aesthetics and flexibility.
Conclusion
The aerospace sector is reputable for its requirement for high-quality standards. Aerospace CNC machining delivers the right machining solutions required by the industry. The machining process allows producing high-quality parts that match the application’s delicacy.
AT-Machining is your one-stop shop for reliable aerospace machining capabilities whenever you need the assistance of experts. We are happy to cater to your aerospace CNC machining needs and meet all design requirements. Our experts often pay attention to safety and manage risk efficiently throughout the product development stages, from prototyping to production. Experience our precision machining services and custom surface treatment options today; let experts handle your project!
