Best Materials for 3D Printing Flight-Ready Aerospace Parts

We know that 3D printing in aerospace enables faster manufacturing of machine components and spare parts. It supports rapid prototype design and iteration and allows for parts to be made in any quantity and shape without excessive material waste. But AM’s biggest draw for aerospace is its ability to produce aircraft parts with equal strength as components manufactured using traditional methods and materials at about half the weight.

Weight reduction or lightweighting is the holy grail of aerospace, allowing planes to fly farther and faster on less fuel. In fact, fuel consumption is reduced by about 1% for every 1,000-pound reduction in aircraft weight², with an associated drop in carbon dioxide production.

To date, AM has had the most impact on aerospace in ground support tooling and non-load-bearing cosmetic parts like interior cabin panels, knobs, and covers. However, the development of advanced filaments reinforced with glass, metal, or carbon fibers that match the strength and temperature resistance of aluminum parts yet are up to 50% lighter is opening new, flight-critical possibilities for AM on aircraft.

In aerospace, safety is always paramount. In addition to high tensile strength, chemical, and thermal resistance, materials certified for in-flight aircraft components must meet the UL 94 standard for safety of flammability with high flame, smoke, and toxicity (FST) properties. Two such resins that meet these standards are polyetherimide (PEI), the most popular being an inflammable polymer from industry leader SABIC, trade-named ULTEM™, and polyetheretherketone, also known as PEEK.

Essentium 3D Printing Filaments for In-flight Applications

Essentium, Inc. offers its own PEI polymer, called Essentium 9085. This high-performance polyetherimide blend is made with a SABIC ULTEM resin base, giving Essentium 9085 excellent long-term temperature performance and toughness. A superior choice for replacing parts made from aluminum, the resin meets UL 94 as well as FAR 25.853 and OSU 65/65 standards for flammability, heat release, smoke density, and toxicity. 3D Printed Aerospace Parts from Essentium 9085 are ideal for aerospace components that must meet strict requirements for strength, temperature performance, and flammability. Examples include lighting systems, electric switches, housings, and bulb sockets.

Essentium PEEK is a semi-crystalline, high-strength polymer that offers high temperature and flame resistance while being virtually impervious to moisture. Essentium PEEK is the product of a partnership with Lehmann & Voss and Company to develop a polyetheretherketone formula optimized for 3D printing. It is the highest performance material in Essentium’s broad filament portfolio. The proprietary formula crystallizes over a longer period and with lower residual stresses than standard-grade PEEK materials for greater printing flexibility and more consistent quality. Essentium PEEK filament is therefore a better choice for applications where tight tolerances are critical, maximum interlayer bonding is desired, or for printing parts with high aspect ratio geometries. PEEK has been used to replace aluminum engine components, bearings, and valves, as well as to create a lightweight conduit to insulate and protect fiber optic cables and the electrical systems running inside aircraft.

It should be noted that both Essentium 9085 and Essentium PEEK require optimal conditions to achieve the highest print quality, including precise filament temperature control in a heated chamber with warmth evenly distributed around a dedicated build space. Essentium not only offers materials certified for aerospace applications, but also the Essentium High Speed Extrusion (HSE) 180•HT 3D Printer optimized for high-temperature applications and materials. It features a high-wear jewel-tipped nozzle capable of reaching 550°C, a sealed multi-modal heated chamber capable of reaching 200°C, and a build area measuring 690 x 500 x 600 mm (WxDxH) to print large parts.