New concepts for the production of energy conversion based components, especially from functional materials, are an indispensable necessity on the way to more sustainable manufacturing. Additive manufacturing, investigated here in the form of selective laser melting (SLM) on thermoelectric materials, promises to become an alternative, which can enable faster and more resource-efficient production compared to the classical processing of these materials.

Thermoelectrics for energy recovery from waste heat or local temperature control belong to one group of functional materials and their improved properties with customized thermal/electrical conductivity properties can benefit end user industries. SLM typically produces objects with small grain sizes, which is particularly advantageous for thermoelectric materials due to increased phonon scattering in the process.

We present our initial work on the commercially used Bismuth Telluride as well as promising class of less critical and highly tunable half-Heusler materials. The work includes fabrication of the starting material as well as their pulverization and additive fabrication of sample bodies to determine physical properties (thermal and electrical conductivity, Seebeck coefficient). But for true sustainability, a supply of printed material based on recyclates is still missing. Fraunhofer IWKS is working on the production of printable powders involving modern recycling processes and offers an insight into circular economy.