Lightweighting components is crucial to the introduction of new, sustainable aircraft and spacecraft. This is where 3D printed parts can be beneficial, as they reduce energy usage and increase the range for new aircraft. In November 2022 Stratasys The company has announced the application of simulation technology Hexagon’s Manufacturing Intelligence division to capture the behaviour of its ultra-lightweight Antero reinforced polyetherketoneketone (PEKK) and its additive manufacturing processes.
According to Stratasys the adoption of AM in structural components is slow because of the safety-critical nature and regulations imposed by the aerospace industry. In the original press release announcing their partnership, Hexagon and Stratasys said that by providing engineering teams the simulation tools to validate the materials that will achieve the required part performance, they are supplying the ‘missing link’ which will enable designers to make breakthroughs.
Foster Ferguson, Global Director of Aerospace at Stratasys told TCT: “When you start to talk about the dimensional accuracy and printing to what the standards are looking for, hitting those specifications is really important. Whatever we’re testing, longevity, UV, heat, fatigue, whatever, characterising that data and giving it to the engineer is critical. That’s why the Hexagon Digimat software is so important to the entire process. We want to able to give confidence with the technical proof on the back end of the print, that the tolerances have been met for the designs for the very unique spacecraft.”
Multi-scale models of Stratasys Antero 840CN03 and Antero 800NA have been added to Hexagon’s Digimat materials exchange ecosystem, with associated print parameters from Stratasys’ aerospace-ready 3D printers. The models let engineers create digital twins to accurately predict how parts will perform when printed using the selected material on an approved aerospace-ready Stratasys machine. Hexagon claims that parts can be digitally simulated with real-world applications and certification testing before physical prototypes are made. The materials are already being used in aerospace engineering, with Lockheed Martin using Antero 840CN03 to create NASA’s Orion spacecraft docking hatch cover.
Speaking about the importance of lightweighted components, such as the ones designed using the simulation software, Ferguson said: “The lightweighting is very important, obviously to engineers who are always looking for ways to save pounds, every pound that you save in spaceflight is very significant in terms of fuel costs. Great aspects of the materials are that they are very fatigue resistant, very strong, and it has electrostatic dissipative properties.”
Ferguson told TCT about the benefits of using simulation software: “Meeting specific requirements and regulations is certainly one of the benefits. Commercial travel has different regulations than space travel. With space travel you’re more concerned about overall safety issues and making sure that when this thing goes out there it’s going to meet the original design specifications and requirements a customer is asking for. In the past we’ve gone through extensive testing on our machines, printing the coupons, testing the filaments and creating a data set that we can publish. We use it in the public forum so that engineers can use a data set and create an equivalency of their own data, based on that foundational data.”
Hexagon says that its Digimat software gives manufacturers the ability to design lighter parts that can match metals in performance and avoid costly ‘overengineering’. Digimat was developed over a ten-year period by the company in collaboration with Stratasys. During this time, high-performance thermoplastics like ULTEM9085 CG, ULTEM1010 and Nylon12CF were characterized and included. Ferguson and Stratasys say that the use of 3D printed material such as PEKKs in aerospace applications is growing.
This story was first featured in the North American and European editions of TCT Magazine in early 2023.