Plasmaschichtentwicklung eines stoffschlüssigen thermoelektrischen Moduls.

The efficiency of future automotive drive trains gains importance due to rising energy costs and the reduction of CO2 emissions. Thermo-Electric Generators (TEG) are devices that convert heat directly into electric energy. The use of waste heat from automotive exhaust systems to generate electricity is explored in the automotive industry as means to reduce fuel consumption. DLR focusses on TEG development with several projects that range from the development of materials to systems integration. Manufacturing of such TEG modules is a multistep process which requires material compati-bility and high manufacturing precision. State-of-the-art TEG modules are force-fit designs which have disadvantages regarding thermal contacting, manufacturing and thermo-mechanical properties. DLR is developing a new firmly bonded TEG introducing plasma spraying to manufacture functional layers of the module. The process is capable of bonding metal and ceramic layers. In addition to the short production time, the improved mechanical bond between plasma-sprayed layers reduces resistances compared to conventional bonding processes. These layers offer low thickness while still having high density and mechanical strength. The legs were brazed on a plasma-sprayed bridge layer to demonstrate the feasibility of the design. It is planned to manufacture full size TEG modules that will be integrated in a test car