ELECTROSLAG TECHNOLOGY
Sokolov V. M., Babyuk V. D., Zhidkov E. A., Shinsky I. O.
Producing of small batches of castings from a nickel-base
heat-resistant alloy using the ESCM process
Problems of combination of processes of electroslag crucible
melting (ESCM) and casting by gasifiable models (CGM) are
considered. This technology is based on remelting metallic scrap
using a molten flux, which is poured out and the metal is poured
into container with a block of models, being under vacuum. The
offered technology is effective both for a single-batch and mass
production of castings. When necessary to increase the rate of
solidification of castings it is recommended to use the new
GAMODAR-process, during which the metal pouring and casting
solidification are realized under the controllable pressure
conditions. The technology is used in production of
heat-resistant alloy components. The feasibility of effective
combination of ESCM processes and different casting technologies
was proved. The CGM is ecologically protected by a special system
of purification of exhausting gases and sand. P. 3
Okhotsky V. B. Removal of non-metallic inclusions in electroslag
remelting
Models of coalescence of liquid phases at wave and viscous
conditions of the melt motion have been developed. Data,
calculated from the models, are correlated with experimental
results. It is shown that the coalescence of non-metallic
inclusions is most probable at their low viscosity. Model of
Handlos-Baron describes appropriately the removal of non-metallic
inclusions from the metal drops during electroslag remelting.
P. 7
ELECTRON BEAM PROCESSES
Movchan B. A., Yakovchuk K. Yu. New approach to producing
microporous materials and coatings by electron beam evaporation
of inorganic substances
The features of the EB-PVD microporous materials and coating
forming were studied. The original method for its producing by
EB-PVD of non-organic materials in vacuum was proposed. The
mechanism of microporous structure forming is considered. The
results of microstructure investigations of the microporous
ZrO2-Y2O3, Al2O3 and NiCoCrAlY condensates and coatings with NaCl
additions are presented. P. 11
Kalinyuk A. N., Zhuk G. V., Trigub N. P. Determination of depth
of shrinkage cavity bedding in ingots of EBRIC of titanium alloy
Ti-6Al-4V
Results of theoretical and experimental investigations of the
process of formation of a shrinkage cavity in ingots of titanium
alloy Ti-6Al-4V in electron beam melting with an intermediate
crucible are given. The fields of temperatures in ingots at a
quasi-stationary condition of melting and solidification of the
last zone of the solid-liquid phase are obtained. Depth of
localization and sizes of the shrinkage cavities in round-section
ingots of 200, 300 and 400 mm diameters at an instantaneous
disconnection of the heat source and a gradual reducing of power
are defined. P. 14
Lesnoy A. B., Demchenko V. F., Zhadkevich M. L. Modelling of
hydrodynamics and heat exchange in solidication of electron beam
remelted ingots
Conjugate model of heat exchange and hydrodynamics in
solidification of the electron beam remelted (EBR) ingot is
considered. The model is based on the equation of a
convective-conductive transfer of energy and a full system of
Navier-Stokes equations with allowance for a thermogravitational,
thermocapillary and forced convection which is caused by a metal
pouring from the intermediate crucible. Heat and hydrodynamic
situation in a solidifying EBR cylindrical ingot was analyzed
using the methods of a computer modelling. P. 17
PLASMA-ARC TECHNOLOGY
Latash Yu. V., Burnashev V. R., Torkhov G. F., Likhobaba A. V.
Peculiarities of producing chromium ingots by the method of
plasma arc remelting
Technology of melting slab chromium billets by the method of a
plasma-arc remelting (PAR) has been developed. The following
plates were produced: 18...24 mm thickness, 90...100 mm width and
100...800mm length. A series of the metal quality examinations
was made. The produced chromium slab samples were compacted into
the consumable billet and remelted in the 90 mm diameter mould
using the PAR method. Electrodes for sputtering in electron beam
furnaces were manufactured from the melted round 360 mm long
ingots. Technical recommendations are given for the chromium
processing. The optimum diagram of remelting was defined. P. 22
Samotugin S. S., Lavrik V. P., Leshchinsky L. K., Solyanik N. Kh.
Plasma treatment of sparsely-alloyed heat-resistant deposited
metal
The effect of a plasma surface treatment on the structures and
service properties of sparsely-alloyed deposited metal was
examined. For all the examined compositions within the ranges of
alloying by a carbon equivalent Cequiv = 0.8...2.1 % the zone of
plasma hardening has a high-dispersed martensitic-carbide
structure, increased hardness and dynamic crack resistance as
compared with the initial state. In addition, with increase in a
carbon equivalent both in initial and hardened state the hardness
of the deposited metal is increased and the crack resistance is
decreasd. P. 26
GENERAL PROBLEMS OF METALLURGY
Grigorenko G. M., Pomarin Yu. M., Orlovsky V. Yu. Kinetics of
nitrogen interaction with liquid zirconium and titanium
Kinetic relationships of nitrogen absorption by liquid zirconium
and titanium from the gas phase are presented. The interaction
reactions were studied by the method of melting in a suspended
state within the wide interval of temperatures and partial
pressures of nitrogen. It is shown that the reactions are
proceeding till the formation of nitrides of the given metals,
gas concentration in metal is described by the second-order
equation and the limiting stage of the process is a
chemical-adsorption link. P. 32
Zelensky V. F., Neklyudov I. M., Lapshin V. I., Sheiko I. V.,
Kobyako I. P., Nademsky V. A., Atramentov V. A., Zeidlitz M. P.,
Klinchuk Yu. I., Cherniy B. P. Production of industrial goods in
Ukraine from scrap of platinum and alloys on its base (Recycling
and refining of scrap)
Technological process of extraction, preparation and purification
of scrap from the industrial waste of platinum and alloys on its
base at the state research-production enterprise of the vacuum
metallurgy of structural materials "Rubin" (Kharkov city) is
described. It is shown that the developed process provides the
minimum losses of noble metals in refining of scrap and producing
noble metals containing not more than 1x10-3 mass % of each
impurity of ignoble metals. The technologies and equipment are
characterized by a good ecology of the processes and low
expenses. P. 38
REVIEW AND SCIENTIFIC DISCUSSIONS
Khokhlov A. A. Letter to the Editorial board concerning the
remarks of V. I. Lakomsky to the article of Khokhlov A. A.
"Investigation of nitrogen interaction with molten steel in
plasma melting", published in journal "Problemy Spetsialnoy
Elektrometallurgii". - 2000. - No. 1. P. 44
Lakomsky V. I. Brief reply to the Editorial board of the journal
"Problemy Spetsialnoy Elektrometallurgii" concerning the A. A.
Khokhlov's letter. P. 45
INFORMATION
Tsykulenko A. K. International Symposium devoted to the memory of
academician Medovar B. I. P. 47
In memory of Trefilov Viktor Ivanovich P. 51
Calendar of International and national events on
electrometallurgy and related technologies for the second
half-year of 2001. P. 52
Advertising. P. 54
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