The university's additive manufacturing department is working on innovative concepts for the powder-based melting of plastics and the combination of materials in material extrusion (MEX).

Joseph Hofmann, research associate at the Chair of Laser-based Additive Manufacturing (LBAM) at the Technical University of Munich, explains the collaboration: "As part of a research project, we analyzed the process-related and design-related influences on multi-material components in additive manufacturing. When the tensile testing machines available to us did not have the right equipment for testing the multi-material tensile specimens produced in the project, ZwickRoell made it possible for us to carry out the tests in their in-house testing laboratory in Ulm at short notice. With ZwickRoell's support, we were able to define suitable test conditions for these innovative specimens and generate reliable test results."

Determining the melt mass flow rate (MFR), the so-called melt flow index, plays an important role in determining the ageing condition of the plastic powder materials used. If the value determined in the PBF-LB/P method (Powder bed fusion of plastics using laser beam) is within a predefined range, the powder can be used for further processes. The test procedure corresponds to method B of the DIN EN ISO 1133 test standard and allows conclusions to be drawn about the weight-related melt flow index of plastics by determining the density. With its nozzle closure, the Mflow extrusion plastometer is optimally designed for testing plastic powders, as this prevents parts of the powder from passing through the test channel in an uncontrolled manner.

When manufacturing multi-material components, the identification of suitable processing conditions is crucial. These are necessary in order to be able to use different plastics in the same process despite different melting points. By determining the flowability of two materials, suitable process temperatures for the MEX process can be determined.

The modular melt index tester is equipped with textXpert III testing software for fast and standard-compliant testing. This ensures effective measurement operation in a university environment with different test systems and changing personnel. As an option, the tester can be extended with a piston displacement transducer for determining the melt volume flow rate (MVR) and automatic, map-dependent parameterization.