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Ni-Mn-Ga-based magnetic shape memory materials were elaborated by spark plasma sintering method. Micron sized particles were prepared by spark-erosion method in liquid argon and liquid nitrogen from preliminary melted magnetic shape memory master alloys Ni-28.5Mn-22.5G at.%. Powders were annealed in H2 gas atmosphere before sintering. Depending on the cryogenic liquids the morphology of particles alternated between spherical solid and hollow balls. The conditions of spark eroded powder elaboration strongly effect on the morphology, martensitic behavior, and structure of sintered samples. In particularly, martensite has 5M structure in bulk material; 14M and non-modulated martensites were found in annealed powders and sintered compacts correspondingly.

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A model has been proposed to describe the potential barrier that appears during interaction of two compacted layers consisting of hydrophilic oxide nanoparticles of different sizes in each layer upon saturation of this structure with adsorbed water. The dependence of the space charge density of the compacted powder material on the density of particles in it has been theoretically calculated. The distribution of the potential over the thickness of contact between two layers consisting of nanoparticles with different sizes has been obtained.