1. Development of 3D printers
In total, three generations of printers were issued during the SPECTRAL project.
The first generation (G1) enabled the consortium to demonstrate the feasibility of printing high temperature polymers such as PEEK, PEKK, Ultem. The G1 printer was delivered to RESCOLL for material validation. Mechanical coupons and calibration cubes were produced to validate the quality of the process and the robustness of the printer.
Some technological limitations were identified. 3NTR then developed a second printer generation (G2) with more powerful and more precise mechanical features, more reliability in terms of thermal control
The G3 printer is currently being produced for commercialization in the near future.
2. Development of high quality materials
In order to evaluate the feasibility of printing PEEK polymers, first tests were done with a special grade of PEEK and a ‘low temperature’ printer. Rapidly, issues with the crystallization of PEEK and interlaminar adhesion were observed.
Several grades of PEEK and fillers were selected. Formulations of PEEK and PEKK filaments filled with carbon fibres and glass fibres were developed and characterized. Among these formulations, four formulations based on CF PEEK and PEKK show good promise for further development.
Special attention was paid at producing high quality filament spools (i.e. non porous, constant diameter) with:
- the set-up of an on-line monitoring device to control filaments diameter and ovality
- their packaging to avoid moisture absorption.
A comparative study of injected polymers vs. printed polymers was performed to obtain their intrinsic thermal and mechanical properties.
The impact of the print path and directions was evaluated to better understand the relation between process and properties. Overall a 20% decrease of mechanical properties was observed, attributed to the influence of interlaminar adhesion and the presence of porosity.
3. One of the objectives of the project was to develop breakaway support materials compatible with high-temperature printing conditions and PAEK polymers. Adhesion tests were carried out to evaluate the affinity of support materials with the print polymer. Preliminary formulations of support materials were obtained and show a good thermal behaviour.
4. RESCOLL developed a database interface architecture capable to create 3D print data sheets, store materials testing data, correlate print parameters to results and allow materials usage tracking.
5. The main stakeholders, competitors and applications were identified by means of a market study. 3NTR and RESCOLL identified their commercial strategy based on key exploitable results. Their offers were positioned on the market to insure a potential market penetration. FFF Spectral printer and PEEK filaments from RESCOLL are well positioned on the market in terms of performances and price.
During the project, partners attended 17 fairs and conferences to disseminate the results of the project and presented one webinar. The G3 printer was unveiled at the Formnext show held in November 2019. Several articles were issued in specialized websites, magazine as well as on partner social media
The main key exploitable results are:
- a FFF printer and replacement parts capable of standing 250°C in the chamber and 500°C at the extrusion head.
- PEEK and PEKK filaments, not reinforced, and reinforced with glass fibers and carbon fibers. These have been fully characterized and can be produced on demand.
- Preliminary formulations of support materials
- A database allowing the storage of original models, the storage of data related to print quality and materials, and the storage of post-print analyses
- A service offer dedicated to FFF additive manufacturing by RESCOLL : filaments custom development, materials characterization and validation, printability/prototyping, and pre-series manufacturing.
