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The DTA and TG study in air of Ti2Al (C1-xNx) and Ti3AlC2 synthesized under Ar 0.1 MPa pressure and densified in thermobaric conditions at 2 GPa, 1400 °C, for 1 h showed that the increase of the amount of TiC layers in Ti-Al-C MAX phases structures leads to the increase of their stability against oxidation: 321 MAX phase Ti3AlC2 are more stable than Ti2AlC and Ti2Al (C1-xNx) solid solutions both before and after thermobaric treatment. The oxide film formed on the surface of the highly dense (ρ=4.27 g/cm3, porosity 1 %) material based on nanolaminated MAX phase Ti3AlC2 (89 % Ti3AlC2, 6 % TiC, 5 % Al2O3) manufactured by hot pressing (at 30 MPa) made the material highly resistant in air at high temperatures: after 1000 hours of exposition at 600 °C it demonstrated a higher resistance to oxidation than chromium ferrite steels (Crofer GPU and JDA types). Due to the surface oxidation self-healing of defects took place. Besides, the Ti3AlC2 material demonstrated resistance against high-temperature creep and after being kept in H2 at 600 °C for 3h its bending strength reduced by 5 % only. At room temperature the Ti3AlC2 bulk exhibited microhardness Hμ = 4.6 GPa (at 5 N), hardness HV50 = 630 (at 50 N ) and HRA = 70 (at 600 N), Young modulus was 140 ± 29 GPa, bending strength =500 MPa, compression strength 700 MPa, and fracture toughness K1C=10.2 MPa·m0.5.

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The features of the physical mechanisms of controlled ion-plasma formation of the new functional nanomaterials are investigated. The technological regimes of formation of functional nanostructured materials under combined impact of several plasma sources are investigated; the structural and electrical properties of the obtained TiN films are studied. The structures of films are studied with scanning tunnelling microscope JSPM-4500/4610 interlocked with an atomic force microscope. As shown, the optimized helicon-arc reactor demonstrates the unique properties and provides controlled lowtemperature formation of the dense regular TiN nanostructures with the sizes from a few to tens of nanometres.Вивчено особливості фізичних механізмів керованого йонно-плазмового формування нових функціональних наноматеріялів. Відпрацьовано тех-нологічні режими формування функціональних наноструктурованих ма-теріялів за спільної роботи кількох джерел плазми; вивчено структурні та електрофізичні особливості одержаних плівок TiN. Структури плівок до-сліджено на сканівному тунельному мікроскопі JSPM-4500/4610, збло-кованому з атомним силовим мікроскопом. Встановлено, що оптимізова-ний гелікон-дуговий реактор демонструє унікальні властивості і забезпе-чує кероване низькотемпературне формування щільних упорядкованих наноструктур TiN з розмірами від одиниць до десятків нанометрів.Изучены особенности физических механизмов управляемого ионно-плазменного формирования новых функциональных наноматериалов. Отработаны технологические режимы формирования функциональных наноструктурированных материалов при совместной работе нескольких источников плазмы; изучены структурные и электрофизические особен-

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High-pressure (HP) synthesis and sintering are promising methods for manufacturing of the bulk MgB 2 superconductive material. The available high-pressure apparatuses with 100 cm 3 working volume can allow us to use the bulk MgB 2 for practical applications such as electromotors, fly-wheels, bearings, etc. We have found that the Ta presence during HP synthesis (especially) or sintering process (in the form of a foil that covered the sample and as an addition of Ta powder of about 2-10 wt.% to the starting mixture of B and Mg or to MgB 2 powder) increases the critical current density (j c ) in the magnetic fields up to 10 T and the fields of irreversibility (H irr ) of MgB 2 -based bulk materials. We observed the strong evidences that Ta absorbs hydrogen and nitrogen during synthesis and sintering to form Ta 2 H, TaH and TaN 0.1 and prevents or reduces the formation of MgH 2 (both with orthorhombic and tetragonal structures). Ta also essentially reduces the amount of impurity nitrogen in black Mg-B (most likely, MgB 2 ) crystals of