Raw materials. Titanium sponge
SURFACE TENSION AND DENSITY OF THE LIQUID SLAG OF ALUMINOTHERMIC MELTING Al-V-Ti-C and Al-Cr-Mo-Si MASTER ALLOYS
V. Chumarev, A. Larionov, D. Taranov, S. Vohmentsev
By method of «maximum pressure in a gas bubble» measured the surface tension and density of slag melts formed during the aluminothermic smelting of Al-V-Ti-C and Al-Cr-Mo-Si. It has been established that in terms of density and surface tension, the actual slags are close to the pure melts of the Al2O3-CaO system corresponding to the oxide concentration. The values of the surface tension of Al-V-Ti-C and Al-Cr-Mo-Si master alloys and interfacial tension at the ligature-slag boundaries are estimated. The magnitude of the interfacial tension (720-730 kJ/m2) at the ligature-slag boundary is typical for the metal-slag system.
Keywords: density, surface tension, interfacial tension, slag, aluminothermic, master alloy.
SEPARATE EXTRACTION OF TITANIUM ORE BY ALLOCATING THEIR TECHNOLOGICAL TYPES
S. Kornilkov, A. Glebov, A. Pelevin, A. Dmitriev
The main results of consolidated laboratory tests for the enrichment and development of batch concentrates from multicomponent and normaltitanium varieties of ore, which showed the best dressability ore, compared with normaltitanium kind of ore. The technologies of enrichment of ores in the separate mining of ores technological types.
Keywords: mineral raw materials base of iron ores, titanium magnetite ore, the ore dressing characteristics, technological types of ores, selective extraction and processing.
ANALYSIS OF CHEMICAL COMPOSITION AND HEAT TREATMENT EFFECT ON STRUCTURE AND MECHANICAL PROPERTIES OF VT35 ALLOY
S. Skvortsova, A. Shalin, O. Gvozdeva, N. Ruchina, A. Volodin, E. Kavchenko
In this work effect of alloying elements content in near-β-titanium alloy VT35 on technological and mechanical properties at the room temperature is studied. It is stated that in order to ensure balanced properties complex introduction of aluminium and major alloying elements should not exceed average value (2.5-3.0% Al; 14.0-15.5% V; 2.0-3.0% Cr; 2.0-3.0% Sn), and other elements content is to be on the lower level (0.5-0.7% of Mo, Zr, Nb each).
Keywords: near-β-titanium alloys, technological plasticity, mechanical properties, alloying, yield strength, upsetting, fastening details.
HYDROGEN ALLOYING EFFECT ON STRUCTURE AND PLASTIC DEFORMATION RESISTANCE OF A PILOT HIGH-MODULUS TITANIUM ALLOY WITH HIGH ALUMINIUM CONTENT
A. Mamonov, S. Slezov, E. Agarkova, A. Neiman, O. Polyakov
In this work the effect of additional hydrogen alloying on structure, phase composition and resistance to hot plastic deformation of a pilot Ti-8.7Al-1.5Zr-2Mo alloy being promising for manufacturing of forcing surgical cutting tools is determined. It is stated that hydrogen alloying to 0.3 and 0.6 wt.% increases the volume fraction of β-phase at the temperature range of a+a2+b-region. It is shown that yield strength of the alloy with 0.3 and 0.6 % H decreases by 115-200 MPa at the deformation temperatures of 800-850°C. Stresses weakening under upsetting of the alloy is regulated by the processes of a(a2)-phase dynamical recrystallization.
Keywords: titanium alloy, hydrogen, hot deformation, yield strength, phase composition, dynamical recrystallization.
DYNAMIC OF STRUCTURAL-PHASE CHANGES DURING ANNEALING IN INTERMETALLIC TITANIUM Ti-Al-Nb ALLOY
A. Zavodov, N. Nochovnaya, E. Alekseev, A. Novak
The paper shows the change of structural-phase state with increasing annealing temperature in the range 850–1150°C. By differential scanning calorimetry (DSC) the boundaries of the phase transformations in alloy VTI-4 were established. At 860°C O-phase plate begins to melt, and at 975°C there is a transformation O→α2, and at 1100°C α2-phase is completely dissolved. Starting from 975°C there are signs of B2 ordering in a β-matrix. Structural-phase composition at each studied temperature was set by methods of optical metallography and X-ray phase analysis. Changes in structural-phase state clearly correlate with the measured values of microhardness. The reduction of the volume of the O-plate leads to a decrease of the microhardness up to 370 HV. The process of matrix ordering on the contrary increase the microhardness of the alloy up to 400 HV. It is shown that the cooling water contribute to an increase of the microhardness values of the two-phase (O+b) region up to 420 HV in comparison with air cooling.
Keywords: titanium intermettalics, orthophase, heat treatment, Ti2AlNb, phase transformation, microhardness.
Semi-products manufacturing technologies
Al-Zr-V MASTER ALLOY: OUT-OF-FURNACE SMELTING AND PROPERTIES
M. Trubachev, S. Vokhmentsev, A. Rylov, V. Chumarev, A. Larionov, S. Zhidovinova
The results of the justification and experimental verification of out-of-furnace aluminum-calciumthermic smelting of Al-Zr-V alloy from zirconium and vanadium oxides are presented. It is shown that the autogenous nature of the melting process is achieved by introducing vanadium oxide into the charge in an amount that provides the ratio V2O5:ZrO2 ≥ 1.0 in it. Samples of Al-Zr-V alloys with a content of 18 to 25% Zr and 36–37% V was melted. The compositions of the charges has been determined, which allows to avoid the phenomenon of stratification of the Al-Zr-V alloy during crystallization, which is negative for the technology of smelting of ligatures.
According to chemical and phase compositions, density (4.4–4.6 g/cm3), melting points (1660°C), the obtained Al-Zr-V alloys meet the requirements for alloying materials for melting titanium alloys containing vanadium and zirconium.
Keywords: zirconium, aluminum, vanadium, oxides, ligature alloy Al-Zr-V, out-of-furnace smelting, properties.
STUDY OF THE DEFORMATION ABILITY BILLETS OF TITANIUM ALLOY GRADE PT-7M
Ya. Kosmatskiy, N. Fokin, .E. Filyaeva, B. Barichko
The work investigates the deformation ability of titanium alloy grade PT-7M. The results of the research used in the development of production technology of hot-pressed pipes.
Keywords: titanium alloy PT-7M, deformation ability, resistance to deformation, extrusion of pipes.
ENVIRONMENTAL IMPACT ASSESSMENT OF THE TITANIUM AND ITS ALLOYS PRODUCTION
N. Manuylova, S. Bulychev, S. Gorbachev, E. Messineva
The article gives a general ecological assessment of the effect of titanium and its alloys on the environment, based on their life cycle. The role of titanium and its alloys as promising materials used in a wide range of sectors of the economy including relating to environmental protection areas are also highlighted.
Keywords: titanium, titanium alloys, life cycle, production wastes, class of hazard, environment, power capacity, water consumption, recycling.
COMPLEX PROBLEMS OF TITANIUM ALLOYS APPLICATION IN THE BASIC TECHNOLOGIES OF THE SIXTH TECHNOLOGICAL STRUCTURE
Yu. Kusakina, M. Mastushkin, L. Fedorova
The article considers the influence of the processes of formation of the sixth technological structure on the prospects of using titanium and its alloys in various industries. A number of promising areas of scientific research in the field of production and processing that satisfy the trends of a new technological structure, including the ecologization of production, are described.
Keywords: titanium alloys, technology, sixth technological structure, safety, ecologization.
Events and anniversaries
To the 70-year anniversary Artemii Popov
To the 70-year anniversary Petr Altman