Additive manufacturing – challenges for non-destructive testing

Discussion during lunch time at the VDI-TUM expert forum 2018 Discussion during lunch time at the VDI-TUM expert forum 2018. © Wenzel Schürmann / TUM

Discussion during lunch time at the VDI-TUM expert forum 2018. © Wenzel Schürmann / TUM

Themed additive manufacturing the VDI-TUM Expert Forum took place at the faculty of mechanical engineering (TUM) on 13 September 2018. The Heinz Maier-Leibnitz Zentrum of the Technical University of Munich represented by Dr. Ralph Gilles and the Association of German Engineers (VDI) Materials Engineering, represented by Dr. Achim Eggert and the VDI Committee of Experts 101 organized the 7th VDI-TUM Expert Forum.

This time, the focus was on non-destructive testing for additive manufacturing. Additive manufacturing is defined as processes with the help of which complex components based on computer-generated data models are constructed from informal starting material. This special type of component manufacturing and the associated design freedom represent a major challenge for the testing technology and the process control.

During the forum, examples with different starting materials such as metals, plastics and ceramics as well as various testing techniques with X-ray, neutron, ultrasound and optical methods (including those based on artificial intelligence) were presented. In addition, new test methods were demonstrated, e.g. allowing changes in shape during the manufacturing process.

Prof. Dr. Peter Müller-Buschbaum, Scientific Director of the Research Neutron Source Heinz Maier-Leibnitz (FRM II) of the Technical University of Munich, and Dr. Achim Eggert welcomed the roughly 80 participants and gave an outlook on the expected topics of the event.

Nine experts from various companies and scientific institutes spoke on the topics of testing and quality assurance of additively manufactured components. During the panel discussion (conducted by keynote speaker Prof. Gerd Witt) as well as in one-to-one interviews the participants used the opportunity to ask questions or to discuss their own problems with the speakers.

The conclusion of the experts: “The technology has to be improved to the extent that deeper insights and higher resolutions in the future are possible!” In addition, it was pointed out the need for the correct parameter choice in advance to enable the customer to receive the goals (in terms of the desired output or method). The challenge with additive manufacturing processes lies in the continuous troubleshooting for improvement, because with the same construction method, there can always be different results.