UDC 669.762.295The Al-Ni-Pt phase diagram studied in the whole compositional region at 1300 and 1100°C. The Al 2 Pt phase found to extend up to at least Al 53 Ni 23 Pt 24 composition, separating the Al 3 Pt 2 and Al 3 Ni 2 phase fields. The Al-Ni β phase dissolves up to 38 at.% Pt at 1100°C, while at 1300°C the β region probably extends between the isostructural CsCl-type phases forming at the Al-Pt and Al-Ni terminals. The AlNi 3 phase (γ′) extends up to 35 at.% Pt at practically constant Al concentration, while the high-temperature AlPt 3 extends up to 15 at.% Ni. A ternary phase is formed in a wide compositional region between the regions of γ, γ′, β, and AlPt 3 . Apart from the AuCu-type structure of this ternary phase earlier reported, also its C-centered orthorhombic superstructure with a fourtimes larger unit cell revealed in the high-Al part of the compositional region.

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The kinetics of wetting double titanium and chromium diboride by iron-based alloys with different chromium content is studied. It is shown that contact angles are formed in such systems over the range 0-10 o . The energy parameters of wetting are calculated. It is established that chromium as a surface-active element promotes Fe -Cr alloy spreading on the diboride surface. The microstructure of the interaction area is studied. It is shown that terminal solid solutions and eutectics are formed in the TiCrB 2 -(FeCr) system. The optimum compositions of the metallic binder are determined for TiCrB 2 -based composite materials.

The authors consider resistance to high-temperature oxidation in composite materials based on titanium carbonitride and double titanium-chromium carbide with metal binders, as well as titanium carbonitride with an aluminum nitride additive, with and without a binder. The oxidation resistance of double titanium-chromium carbide powders with a metal binder is studied in their initial and clad forms. Micro-x-ray-spectral and petrographic analysis is used to identify the composition of sample surfaces after oxidation.

The aim of this study is to improve the heat resistance performance of polyurethane based adhesives for the manufacture of shoes. Four polyurethane adhesive compositions most used in the domestic shoe industry have been investigated: PU-503, VU-252, KYSPO-1 and D-274. The main components of polyurethane compositions are urethane rubber, zeolite, ethyl acetate and acetone. It has been found that modification of VU-252, KYSPO-1 and D-274 with zeolite in the amount of 0.5-1% allow to increase the heat resistance to 150° C while that of PU-503 - to 200° C. Besides it has been found that adhesive compositions can be recommended for the manufacture of special fire-resistant shoes that could withstand high thermal loads.

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The ligature for finishing of base steel 3H3M3Ftype for obtaining steel 4H3N5M3Ftype with adjustable austenitic transformation is developed in the article. The phase-structural state of steel in the cast state is investigated. The uniform distribution of alloying components on the body of grains is shown. It was found that the investigated hardened steel is softening above the tempering temperature of 620 °C, because the heat resistance of steel decreases (below 40 HRC). It was developed a 3H3M3F base steel ligature for steel production with adjustable austenitic transformation of 4H3N5M3F brand. Ingots (ligature of the Fe―Ni―Mo―V―Mn system) weighing 25 kg were obtained. The ligature was obtained by means of an induction furnace in a casting mold. The temperature of the metal in the furnace before release was 1550 °C. The duration of refining did not exceed 20 minutes. The phase-structural state of cast steel is studied. The uniform distribution of alloying components on the body of grains is shown, as well as the absence of coarse carbide eutectic in metal. This allows to reduce energy-intensive technological operations (diffusion annealing, forging) for the die toolsmanufacture. The presence of martensitic structure in the steel in the cast state of the investigated ingot requires the main thermal operation — annealing. It is established that incomplete annealing at a temperature of 750 ± 20 °C under the condition of partial recrystallization of the investigated steel allows to improve the mechanical processing (cutting) for the production of the die tool. It was determined that the investigated hardened steel hardens above the tempering temperature of 620 °C, because the heat resistance of steel decreases (below 40 HRC). Thus, a die tool of the investigated steel for hot deformation, capable of operating up to the temperature of 620 °C. Keywords: steel, ligature, temperature, structure, hardness.