IPF: New materials and applications for 3D printing

Research institutions and industry partners from Germany and South Africa are cooperating in the new MultiMat³ project as part of the European Union's M-era.Net program. Together, they are developing optimized and new materials for use in additive manufacturing technologies.

For MultiMat³, one of the first Arburg Freeformers with three so-called "print heads" for melt preparation was installed at the IPF. (Source: Arburg)

Additive manufacturing technologies and devices are already available in a number of varieties. At present, however, only selected polymer materials can be used in 3D printing. In addition, only a limited knowledge and data base exists on the specific process-structure-property relationships, which hinders selection of appropriate materials and processes, as well as product quality reliability. Furthermore, special challenges are the successful processing of semi-crystalline polymers, the avoidance of shape changes (warpage) and the sufficient interfacial bonding within additively manufactured components. These issues are being addressed in the three-year MultiMat³ project by scientists from the Leibniz Institute of Polymer Research Dresden e.V. (IPF) and the University of Pretoria, South Africa, together with the industry partners:

• Arburg GmbH & Co. KG, Germany
• Allod Werkstoff GmbH & Co. KG, Germany
• Microfol Compounding GmbH & Co. KG, Germany
• Greenfield Innovation (Pty) Ltd (South Africa)

Project coordinator is the new speaker of the TPE-Forum, Dr. Ines Kühnert, IPF. "I am delighted that in the new project we will be able to continue our many years of successful collaboration with partners in South Africa, especially on new nanocomposites, and that together with strong industrial partners we will be able to contribute our special expertise at the interface of chemistry and processing technology to the rapidly growing and very promising field of additive manufacturing," says Kühnert.

Test specimens produced by AKF at IPF (Source: IPF Dresden/R. Fechter)

Two already existing AM technologies were selected for the project: firstly, Fused Filament Fabrication (FFF), which is one of the most cost-effective AM processes and has therefore already established itself in private, non-industrial application environments. On the other hand, the "Arburg Kunststoff-Freiformen" (AKF) developed by the project partner Arburg is used, which shows advantages especially for the combination of polymer materials due to the applicability of commercially available plastic granules and the direct path from the granulate to the melt drop layer structure. For this reason, one of the first freeformers with three so-called "print heads" for melt preparation was installed at the IPF for the project.

In the first project phase, selected polymer materials established on the market will be tested for both FFF and AKF processes in order to obtain important basic data for the design of new material concepts and technological boundary conditions.

At the same time, the development of so-called LDH nanocomposites is being advanced together with the South African partners in order to be able to process nanoparticle-optimized plastics (e.g. with reduced warpage potential) by means of additive processes. The focus in the project is to develop new material combinations for FFF and AKF and to demonstrate their application potential for additively manufactured products. Although the development of new polymer materials is initially based on the requirements for existing AF processes, it is planned to further optimize the processes and equipment technology for the new materials and material combinations in the course of the work in the project, for which the involvement of machine manufacturers will be of great benefit. Finally, it is planned to manufacture demonstrators and transfer the knowledge gained from these to real components using new polymer materials.

The subprojects are funded in Germany by the Saxon State Ministry of Science, Culture and Tourism (SMWK) and in South Africa by the Department of Science and Innovation (DSI).

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