If there’s one thing that has become clear in the recent evolution of additive manufacturing technologies is that they will not replace traditional manufacturing processes. Instead, they will complement and, in many cases, enhance them. Stratasys is showcasing this reality at JEC World, where it revealed how Spanish composite solutions company IDEC has leveraged AM to cut the time, cost and material waste associated with composite molding processes.
IDEC, a composites company that specializes in aerospace applications, used Stratasys’ F900 Production System 3D printer to achieve the aforementioned efficiency objectives in a government-funded project. The project was organized to investigate the potential of Resin Transfer Molding (RTM) technology and involved testing a new composite material and its molding process to produce a curved aircraft wing.
Working in collaboration with advanced prototyping company Wehl & Partner, IDEC used 3D printing to produce a preform tool made from a high-temperature and pressure-resistant material (ULTEM 1010 resin). The polymer preform was designed to replace aluminum in a tooling application that required an electric current.
Typically, IDEC’s preform tools are made from aluminum or epoxy resin, which facilitate the composite lay-up process into the mold and accelerate the curing process. Using this method, the composite fiber is laid on top of the preform and the tool is heated to take the shape of the mold.
In this particular case, however, the composite material was to be heated using an electric current, which made a conductive aluminum preform impossible to use, as it would prevent the current from effectively going through the composite fibers. The more traditional epoxy resin preforms were also unusable as they did not have the necessary resistance or stability to withstand temperatures exceeding 140°C.
Wehl & Partner used its in-house Stratasys F900 Production System 3D printer to produce the large-scale preform tool from ULTEM 1010 resin—a non-conductive material with excellent chemical, heat and pressure resistance.
“This project required high temperatures of between 150°C and 180°C to heat the fabrics directly, which made the Stratasys FDM additive manufacturing and the use of ULTEM 1010 resin, in particular, the perfect choice,” said Diego Calderón, Structural Analysis Manager at IDEC. “Although there are epoxy resins resistant to such high temperatures, these are very expensive, and would not have been financially viable.”
The integration of additive manufacturing at this stage in the production process enabled IDEC to achieve a massive time reduction: while the preform tool production process would have traditionally taken about a month, the timeframe was reduced to just 60 hours.
“Stratasys additive manufacturing enabled us to produce the preform tool in just 60 hours,” said Calderón. “With CNC machining, it would have taken at least four weeks to produce this type of part. Indeed, not only did we slash the production lead-time on the preform tool, but we also expedited the whole composite molding process.
“In fact, with ULTEM 1010 resin, we reduced the composite heating stage from one hour to only ten minutes by flowing the electrical current directly through composite fabrics. This would simply not have been possible without Stratasys FDM additive manufacturing.”
Thanks to the dramatic time savings and the 3D printing process, IDEC was also able to cut its costs by 67% compared to the cost of CNC machining the aluminum preform.
Ultimately, the use of Stratasys’ 3D printing and ULTEM 1010 resin enabled IDEC to produce a preform tool with the desired mechanical properties for the RTM process. The 3D printed preform is reportedly strong enough to be used for at least 25 cycles, making it superior to epoxy preforms and those made using other 3D printing materials.