3D printing, also known as additive manufacturing, is highly valued in the aerospace industry. In an industry where weight or drag reduction can lead to huge cost savings, 3D printing has enabled aerospace manufacturers to create lighter and more fuel-efficient aircraft in a more cost-effective manner. The aerospace industry was one of the first industries to widely adopt 3D printing in the manufacture of key components, and the process has redefined the boundaries of design and manufacturing. Aerospace engineers were instrumental in the development of the 3D printing process, and the industry continues to reap the benefits today as 3D printing matures as a manufacturing process.
From jigs and prototype tooling to end-use parts like nozzles and control consoles, 3D printing in aerospace can be used to both aid the manufacturing process and satisfy particular applications within an aircraft. This article will discuss 3D printing in aerospace, the materials and processes used, and its different applications.
What Is 3D Printing?
3D printing, also known as additive manufacturing, is a manufacturing process that creates parts layer by layer until the entire three-dimensional part is complete. It is the opposite of subtractive manufacturing processes like CNC (computer numerical control) machining where the material is removed from a workpiece to create parts. 3D printing can be used to manufacture trinkets, simple tools, and advanced components used in several industries such as aerospace, automotive, medical, machinery, and more. While 3D printing technology has existed since the 1980s, its use has exploded since the start of the 21st century as additive manufacturing has become a sound alternative to produce parts that require several processes to manufacture.
When Did the Aerospace Industry Start Using 3D Printing?
The aerospace industry was one of the first industries to implement 3D printing in 1989. Since the inception of 3D printing technology in the 1980s, the aerospace industry has been one of the largest contributors to the development of 3D printing processes and technology. Today, the industry remains one of the largest beneficiaries of the process and accounts for nearly 16% of the total revenue generated by the additive manufacturing industry.
How Did 3D Printing Start in the Aerospace Industry?
The origin of 3D printing in the aerospace industry dates back to the late 1980s. At the time, the largest benefactors of 3D printing were the US military and the defense industry. These two organizations widely used plastics as a cheaper alternative to metals to conduct testing and simulation of various aircraft systems and components.
3D printing was mainly used for prototyping and testing in the aerospace industry until the mid-2000s when it became possible to 3D print flame-retardant plastics through processes like selective laser sintering. As advancements in 3D printing continued throughout the first two decades of the 21st century, its use in aerospace applications expanded. Now it is used for applications throughout the aerospace component lifecycle, including: prototyping and validating designs, tools, jigs for aircraft maintenance, end-use parts in jet engines, and aircraft interiors.
What Kinds of Materials Are Used in 3D Printing for Aerospace Applications?
A number of different materials are used in aerospace industry applications. Common materials used are listed and described below:
Ceramics are inorganic, non-metallic materials. They are great for aerospace applications due to their corrosion resistance, light weight, and wear resistance. However, ceramics are exceptionally hard and brittle, making them difficult to fabricate into parts. Kaolin and porcelain clay are two examples of ceramics that can be 3D printed to make parts. Ceramic 3D printing can be used to make satellite mirrors which are made from silicon carbide, with the goal of reducing weight and improving stiffness to strength ratio.
2. Carbon Fiber
Carbon fibers are long, exceptionally thin but strong strands of carbon atoms. Carbon fiber composites are ideal for aerospace applications since it is as strong as steel but lighter than aluminum. This allows manufacturers to improve aircraft performance by integrating 3D-printed carbon fiber parts into aircraft frames and structures. However, carbon fiber is expensive and difficult to produce, which limits the potential applications it can have in the aerospace industry.
Glass is an amorphous material that is made by the rapid quenching of a molten mixture of silica and other ingredients. Glass is a transparent and brittle material that has been used since ancient times. While it may often be associated with windows, 3D-printed glass is not used for windows in aircraft. Instead, glass-filled filaments and powders are often used to reinforce plastics and to make glass composites which are helpful in reducing aircraft weight.
Metals are naturally occurring ductile and lustrous materials that are excellent conductors of heat and electricity compared to other materials. Metals like aluminum and titanium are widely used in aircraft due to their corrosion resistance and high strength-to-weight ratios. 3D-printed metals are used in engine components, frames, structures, and electronics equipment. A major downside of metals is that they are heavy. Too much metal in an aircraft can adversely affect aircraft performance and fuel efficiency. Figure 1 is an example of a 3D printed turbine propeller: