POSSIBILITY OF THE METHOD OF EXPLOSIVE ELECTRON-BEAM EVAPORATION-CONDENSATION IN VACUUM TO OBTAIN THE REFRACTORY AND COMPLEXLY DOPED COMPOUNDS FOR VARIOUS PURPOSES

54 ɆȺɌȿɊȱȺɅɈɁɇȺȼɋɌȼɈ ɌȺ ɆȺɒɂɇɈȻɍȾɍȼȺɇɇə DOI: 10.20535/kpi-sn.2019.4.180747 UDC 004.942, 57.087 I.M. Hrechaniuk1, O.V. Khomenko2 , G.A. Baglyuk2 1 Scientific and Production Company “ELTECHMASH”, Vinnytsia, Ukraine 2 Frantsevich Institute for Problems of Materials Science, NASU, Kyiv, Ukraine correspondingauthor: POSSIBILITY OF THE METHOD OF EXPLOSIVE ELECTRON-BEAM EVAPORATION-CONDENSATION IN VACUUM TO OBTAIN THE REFRACTORY AND COMPLEXLY DOPED COMPOUNDS FOR VARIOUS PURPOSES Background. The method of explosive electron-beam evaporation-condensation of materials in vacuum opens up new possibilities for obtaining materials containing components, with a significant difference in the elasticity of the vapor, as well as complex alloyed compounds. This technology is promising for the production of various types of materials of controlled chemical composition in the form of powder products. Objective. The purpose of the paper is to study the possibilities of the method of electron-beam explosive evaporationcondensation of materials in vacuum to obtain in granular and film form refractory and composite materials based on tungsten and copper, and complex alloyed materials based on titanium. Methods. The method of explosive evaporation-condensation was used to obtain vapor-phase refractory, composite and complex alloyed materials based on the WC—W2C, Cu—W and Ti—Si—Zr—Nb systems. The experiments were carried out on the L-4 electron-beam installation, which was developed by the Scientific and Production Company “ELTE¯HMASH” (Vinnytsia, Ukraine) in cooperation with the Frantsevich Institute for Problems of Materials Science, NAS of Ukraine. The changes in the chemical composition and morphology of obtained products depending on the deposition conditions in vacuum were studied. Results. For the first time, refractory alloys and composite materials based on tungsten and copper and complex alloyed compounds based on titanium were obtained in granular form by explosive evaporation-condensation in vacuum. Using this technology makes it possible to control the chemical composition and morphology of the produced powder products, widely used in various fields of science and technology. Conclusions. The technological conditions for the production of materials containing components with a significant difference in vapor pressure by the method of explosive evaporation-condensation in vacuum are determined. The method allows obtaining granular and film deposition products with refining of materials with respect to oxygen and some metal impurities. Keywords: electron-beam technology; method of explosive evaporation-condensation in vacuum; tungsten and copper based refractory and composite materials; complex alloyed materials based on titanium. Introduction Dispersed powders of metals and alloys play an important role in solving problems of creating material and products with controlled complex of properties. Material based on eutectic mixture of tungsten carbides WC and W2C is widely used as a component of wear-resistant surfacing material, working under conditions of intense abrasive wear under moderate impact loads, for example, in roller bits, drill pipe locks, and other applications [1]. Materials of the Cu—W system are traditionally manufactured by powder metallurgy and are widely used in the electrical industry. Traditional technology of producing electrocontact materials enclude multi-stage process for obtaining a mixture of powders of the required chemical composition, compressing them and conducting high-temperature processing in ©TheAuthor(s). ThearticleisdistributedunderthetermsofthelicenseCCBY4.0. controlled gas media (restorative, neutral) or in vacuum. Until recently, the manufacturing technology of these materials were based on powder metallurgy high-cycle methods, including such technological operations as the production of powders, their subsequent compaction (cold or hot pressing); high temperature treatment; and/or deformation processing of obtained materials and products [2]. Investigation of the conditions for obtaining Ti-based complex-alloys is dictated by a unique complex of properties, which makes them an indispensable component for medical purposes [3]. Recent studies have shown that a compromise between the required set of mechanical properties and biomedical constraints can be obtained by doping Ti with the most biocompatible elements such as Si, Nb, Zr, and Mo, which are stabilizers of the D-phase of Ti [4]. 55 ɆȺɌȿɊȱȺɅɈɁɇȺȼɋɌȼɈ ɌȺ ɆȺɒɂɇɈȻɍȾɍȼȺɇɇə Electron-beam technology of evaporation-condensation of materials in vacuum promotes new opportunities for obtaining composite powders (from nanoscale to several hundred micrometers) in a wide range of quantity components, phases, dispersed inclusions, and other parameters [5]. Since the dependence of vapor pressure and evaporation rate on temperature for various metals can be quite large, fractionation in composition is one of the main problems of evaporation-condensation in vacuum for obtaining materials which have components with a significant difference in vapor pressure. It is known that during evaporation of alloys consisting of components with different vapor elasticity, the degree of their fractionation in composition decreases with increasing temperature and this regularity was used by Harris and Siegel when developing the high-speed method of evaporation of alloys [6]. The method consists in the fact that particles of finely ground material (alloy of the required composition or mixture of components) are uniformly fed to the evaporator, and heated to the temperature of intensive evaporation of the most difficult volatile components of the alloy. Due to the ultra-fast heating of the alloy, its explosive evaporation occurs, which is characterized by matching the composition of the starting material, vapor over the evaporator and condensate. The research in this direction was started at 7 6 8 the Frantsevich Institute for Problems of Materials Science (NASU) in collaboration with the Scientific and Production Company “ELTECHMASH” (Ukraine). Problem statement The main purpose of these studies is to discover the possibilities of obtaining powder products of different chemical composition, including components with a significant difference in vapor elasticity by the method of explosive evaporation-condensation in vacuum. Results and discussion SPC “ELTECHMASH” developed a new electron-beam installation modification L-8 (Fig.1), which allows solving a wide range of tasks, in particular, to simulate various versions of structures in order to test modern concepts of physics, chemistry and solid mechanics and create materials with a given structure and properties for solving a variety of applied problems. For the first time, a successful attempt was made at this installation to obtain, by explosive evaporation-condensation in vacuum, powdered composite materials consisting of components wit (...truncated)