HSS Material Network - Proof of Concept TPU Launhardt

The HSS Material Network is an interdisciplinary network of selected experts dedicated to making the development and qualification of new polymer materials for the additive manufacturing process High Speed Sintering (HSS) more flexible and faster.

The VX200 HSS from voxeljet is designed as an open source 3D printing system and provides full access to process parameters and temperature management to best match the additive manufacturing process and material. The HSS Material Network offers customers a flexible and low-risk outsourcing option for material development of additive manufacturing technologies. The addition of the competencies of the HSS Material Network partners enables companies of all sizes to receive unique support, from an initial suitability assessment, through specific development and parameterization, to certification or market-ready qualification of the material. Here we present our partners, projects and proof of concepts.

Proof of Concept III – TPU Launhardt

Customer/material manufacturer: Launhardt GmbH
Development & Qualification: Project Group Process Innovation of Fraunhofer IPA / Chair of Environmental Production Engineering of the University of Bayreuth

2. For which applications (industries, products) is your TPU suitable?

The Launhardt TPU enables the production of a wide variety of parts such as bellows, sealing profiles, machine feet or even shoe soles and orthopedic parts. The soft and rough surface enables the production of haptically appealing surfaces. For instance, the material can be used to imitate leather.

The possibility of chemical smoothing results in a sealing of the surface and furthermore the functionality of media-tight parts (e.g. sealing elements).

3. Which properties of your TPU can be influenced/optimized by additive manufacturing? What role do grayscales play? Does this expand areas of application? If so, to what extent (markets, products)?

With the application of grayscale printing, the Shore hardness can be directly influenced. In this way, parts with stiff and softer structures can be economically implemented in one part. These graded part properties could be used, for example, for elastic and damping lattice structures such as those used for sports articles (shoes, backpacks, saddles, etc.).

4. What are the strengths/weaknesses of HSS in processing your TPU? Especially compared to other additive technologies such as SLS?

Since TPU absorbs the energy for melting very slowly, the HSS process is particularly suitable for clean and stable processing of TPU. Unlike SLS, the energy is introduced physically slowly, so that the thermoplastic material has sufficient time to melt and bond interlaminar without producing smoke. Since this does not reduce the processing speed, the HSS process enables economical and stable processing of the Launhardt TPU.

5. Which further steps are planned after the material analysis? Will the material be fully developed/qualified for HSS?

Since we also process our soft TPU material ourselves (previously in SLS) and thus achieve the best possible part properties for our customers, we are planning to diversify into new and promising powder-based additive manufacturing processes. In particular, the HSS process is very attractive, as the process is fast, predictable and stable and enables individual part properties.

The TPU from Launhardt GmbH is one of the softest on the market. In combination with HSS grayscale printing, the material properties can be influenced in all three dimensions by changing the printed ink volume. This makes it possible to incorporate different material properties, such as hardness lines, into a component regardless of the geometry.