With global temperatures being on the rise for the last nine consecutive years, the increasing global demand for cooling and refrigeration presents a critical challenge and signifies the necessity for the exploration of more energy-efficient solutions beyond the conventional vapor-compression technique. Magnetic cooling is seen as a promising alternative, as magnetic refrigeration systems show an increased energy efficiency.

In recent years, Ni-(Co)-Mn-X Heusler alloys have gained increased attention, as they show a large inverse magnetocaloric (MCE) and conventional elastocaloric effect (ECE), making them a promising candidate for magnetocaloric (MC) and multicaloric (MuC) cooling. The caloric effects arise from a first-order magnetostructural phase transition (FOMST) from a high-magnetic austenite phase to a low-magnetic martensite phase. To optimize the multicaloric performance of these materials, the FOMST needs to be tailored, which requires a comprehensive understanding of the influence of the microstructure.

In this work, we offer a systematic study on the influence of composition and microstructure on the first-order magnetostructural phase transition and the mechanical properties in Ni-(Co)-Mn-X (X = Sn, Ti) Heusler alloys. Heusler alloys will be synthesized from scratch by arc melting. Subsequently, using melt-spinning and hot-compaction, samples with anisotropic microstructures will be produced, which will be characterized by microstructural, chemical and magnetic analysis as well as by mechanical testing.

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