In this work, the directed crystallization of glass-coated magnetic microwires of Co-rich composition is realized with the aim to develop a novel technique for micro-magnet fabrication. The onset of the process is caused by local overheating above the primary crystallization temperature while the rest of the wire sample is at the temperature slightly below the crystallization temperature. This creates the conditions for spontaneous formation of microcrystallites at the wire edge and the movement of the crystal-amorphous interface along the wire. It was found that the directed crystallization is possible in a narrow temperature interval of 5-78 near the crystallization temperature. The effect of the directed crystallization on the magnetic properties is evident from a giant increase in coercivity, up to 1000 times. The directed crystallization was also assisted by application of a magnetic field which resulted in greater increase in coercivity, up to 1500 times and the coercivity value reached 69400 A m À1 . For comparison, at a standard crystallization the coercivity increases by 8-10 times being in the range of 2000-4000 A m À1 . The developed micro-magnets can find a range of applications in miniature sensors, actuators, and manipulators.

The method of modernized ion-plasma sputtering produced metastable states, including nanocrystalline and amorphous phases in films of Fe-Ag, Fe-Bi, Fe-Ag-Bi, Fe-Co-Ag and Ni-Ag alloys whose components do not mixed in the liquid state. The periods of the crystal lattices and the dimensions of the crystallites of the nonequilibrium phases in the fresh-sputtered state and after the heating are determined. The temperatures of the beginning and the end of the decomposition of metastable phases are established when heated at a constant rate. The electric and hysteretic magnetic properties of films in freshly dusted and thermally processed states are measured. The compositions and conditions for obtaining films with low values of the temperature coefficient of electrical resistivity (~ 10-5 K-1) and high coercive force (HC ~ 150 kA/m) are established. Such films can be promising for use as thin-film precision resistors and magnetic information carriers with an increased recording density.

The quantitative estimation of maximum level of cooling rates in the process of casting microwires in glass insulation is given. The shown possibility of nonequilibrium formation of microwire substance is due to the influence of an amorphous substrate in the form of glass insulation. The amorphous state in the case of thin microwires with cast iron vein Fe‒20 at.% C confirms the implementation of an increased (compared to splat-quenching) level of nonequilibrium formation of microwires in combination with updated rates of cooling and increased degree of supercooling of liquid microwire vein.

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