Elastocaloric cooling systems can evolve into an environmentally friendly alternative to compressor-based cooling systems. One of the main factors preventing its application is a poor long-term stability of the elastocaloric material. This especially applies to systems that work with tensile loads and which benefit from the large surface area for heat transfer. Exerting compressive instead of tensile loads on the material increases long-term stability—though at the expense of cooling power density. Here, we present a heat transfer concept for elastocaloric systems where heat is transferred by evaporation and condensation of a fluid. Enhanced heat transfer rates allow us to choose the sample geometry more freely and thereby realize a compression-based system showing unprecedented long-term stability of 107 cycles and cooling power density of 6270 W kg−1.

Electronics (particularly power electronics) are the core element in many energy-related applications. Due to the increasing power density of electronic parts, the demands on thermal management solutions have risen considerably. As a novel passive and highly efficient cooling technology, pulsating heat pipes (PHPs) can transfer heat away from critical hotspots. In this work, we present two types of small and compact PHPs with footprints of 50 × 100 mm2, thicknesses of 2 and 2.5 mm and with high fluid channel density, optimized for cooling electronic parts with high power densities. The characterization of these PHPs was carried out with a strong relation to practical applications, revealing excellent thermal properties. The thermal resistance was found to be up to 90% lower than that of a comparable solid copper plate. Thus, a hot part with defined heating power would remain at a much lower temperature level and, for the same heater temperature, a much larger heating power could be applied. Moreover, the dependence of PHP operation and thermal properties on water and air cooling, condenser area size and orientation is examined. Under some test configurations, dryout conditions are observed which could be avoided by choosing an appropriate size for the fluid channels, heater and condenser.

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Nanometerscale textured layers were achieved by annealing corresponding elemental layers, deposited in nanometerscale thickness which fits to the intended stoichiometry of the resulting compounds. The compound formation as well as the accompanying thermoelectric properties are reported. The compound formation corresponds in particular to the evolution of the Seebeck coefficient.