Cellular metals are highly advanced materials that are often developed for very specific applications. The development and production of these materials are generally very complex and costly. Especially the manufacturing is coupled with high energy requirements.

Due to these constraints, applications with cellular metals are increasingly relying on utilizing not just one specific property of these materials, but the entire portfolio of properties wherever possible. Many applications with cellular metals are aimed at the high lightweight construction potential in combination with a high energy absorption capacity (e.g. vibration damping) or a defined heat conduction (heat exchanger).

New technologies help to create process chains to produce cellular materials more effective or completely redesign them and open new fields of application. Generative processes such as wax printing and laser beam melting offer approaches for completely rethinking the manufacturing process for open-cell metals. Wax printing enables the production of designed open-cell structures and completely replaces models based on PU foams with stochastic cell distribution. With the laser and electron beam melting process, completely new manufacturing methods are available.[1]

Closed cell aluminum foams are characterized by their low density and high vibration damping capacity. Assemblies in machine tool construction continue to benefit from these foams.[2]

The drastic shift in automotive engineering from combustion technology to electric drives enabled a market opportunity for battery boxes made of sandwiches with a closed-cell aluminum foam core. In these applications the task of the aluminum foam is protecting the batterie cells from mechanical damages and overheating by temporarily storing waste heat.[3]

However, production processes that have been evaluated and tested over many years, such as those known from closed-cell metal foams, are also being further developed. Current research work is aimed at further homogenizing the pore structure making it more predictable.[4]

The presentation will describe new developments in the field of open and closed-cellular metal foams, which are being promoted at the Fraunhofer IWU, and highlight the associated potential and applications.

References
[1] C. Drebenstedt, C. Hannemann, J. Hohlfeld, S. Siebeck, T. Hipke, D. Kibaroglu; Materials Research Proceedings, 2024, 39, pp 25-31.
[2] U. Jehring, S. Siebeck, J. Hohlfeld, P. Quadbeck, O. Andersen, T. Weißgärber; 10. Landshuter Leichtbau-Colloquium, 2021, pp 60-74
[3] R Schmerler, C. Drebenstedt, M. Machhammer, G. Gong, P. Wolf; IOP Conf. Ser.: Materials Science and Engineering, 2023, DOI 10.1088/1757-899X/1284/1/012046.
[4] S. Siebeck, M. Trautmann, J. Hohlfeld, T. Hipke, G. Wagner; Key Engineering Materials, 2019, DOI 10.4028/www.scientific.net/KEM.809.320.