In the past, 3D printing was mainly used for prototyping and product testing. Hence, it is closely associated with the name Rapid Prototyping, i.e. fast, precise and repeatable additive manufacturing of elements used for product analysis. Today, each of us can become a user of a 3D printer, and the quality of manufactured elements has improved significantly. As a result, 3D printed models can act as end products in many industries, including the aviation industry.
Why is 3D printing so important in the aviation industry? The desire to reduce the weight of elements, use more durable materials or improve design requires constant testing. 3D printing is the fastest method of prototyping, that is why it gained importance in the industry.
The aviation industry is a huge branch of the economy, including commercial, industrial and military applications. It is a huge machine, consisting of many departments, for example, those dealing with the design, production, operation and maintenance of airplanes and spacecraft. Aviation is the driving force behind the development of 3D printing, since many aircraft components are manufactured using AM. This applies to both prototypes and end-use components.
The use of additive technology in the context of military aircraft and military equipment allows reducing supply chain constraints, decreasing the amount of stocked items and minimizing the amount of waste material compared to traditional manufacturing methods. All in all, 3D printing saves storage space, time and money.
The table below shows the advantages and disadvantages of additive manufacturing and traditional manufacturing methods in the context of the aerospace industry.
| Additive manufacturing | Traditional manufacturing methods (CNC) | |
| Cost | Production of elements at the cost of materials | Additional costs include moulds and dyes preparation and finishing |
| Time | Fast production time- usually up to several hours | Long time, depends on the complexity of the mould, stock and supply chain |
| Consumption of resources | Optimum material quantity needed | High consumption |
| Product | Possibility to produce products with a complex geometry | Limited production, need to combine several elements into one system |
| Post-processing | Not always necessary | In most cases required |
| Quality of material | PEEK, ULTEM- properties similar to steel | Load-bearing parts |
| Material losses | Low/ None | High |
| Prototyping | Rapid prototyping | Very expensive and time consuming |
| Airspace use | Possible with high temperature filaments, with low weight and high mechanical resistance | Difficult |
The most important reason for optimizing aircraft and spacecraft components is to reduce their weight. This is because the machine’s lighter weight reduces fuel consumption and therefore emissions. It also increases the load capacity, speed and even safety. Due to the fact that 3D printed elements are produced layer by layer, it is possible to create more complex structures, reducing the number of components and thus the weight of the model. Air ducts, wall panels, seat frames and even engine components can be manufactured additively, allowing for a significant reduction in the weight of the aircraft.
Airbus is the record holder in the number of 3D printed elements among airplanes. In the new A350 XWB, more than 1,000 components have been additively fabricated with ULTEM 9085, a thermoplastic polyetherimide. The material has all the necessary certificates and meets the relevant standards of non-flammability and non-toxicity. The material is characterized by high mechanical strength, obtained by a good strength-to-weight ratio, thanks to which its properties are similar to steel. The use of additive technology made it possible to optimize production and shorten the time of making elements.
Another example of the use of 3D printing in the aerospace industry includes NASA, where a space rover was designed and tested. The device is equipped with a pressurized cabin and consists of 70 elements made additively in the FDM technology. These include fireproof vents, housings, fixtures, doors, bumper and many other customized elements.
Due to the fact that aircraft and spacecraft must have appropriate safety certificates, materials used in the aviation industry must also meet the relevant standards. Aviation plastics must be thoroughly tested for a variety of properties such as dimensional stability, strength, viscosity, heat resistance and moisture resistance. Designing such machines is a long and tedious process, therefore many concepts are suspended at the stage of specialized research. Among others, delamination and cracking of prints due to specific factors are being improved. To prevent damage to models, technologists are working on reduction of the porosity of additively manufactured parts, reducing the number of hollow places caused by shrinkage, oxidation or other leaks. These problems can be minimized by adding carbon or glass fibers to the filament, which will improve the mechanical properties and improve thermal conductivity of the model.
Additive technology is revolutionizing many industrial sectors, including aviation. 3D printing is an excellent method of prototyping and design verification. Modern materials and the possibility of their modification allow us to meet the high requirements of this industry. Weight and safety are the main factors that need improvement. Additive manufacturing allows one to optimize these two components easily and quickly. So it is only a matter of time when 3D printing will replace traditional manufacturing methods.