Markashova L. I., Grigorenko G. M., Valevich M. l. and Petrov S. V. Features of the structure of surface metal layers in railway wheel treads after plasma treatment // Paton Welding Journal. – 2005. – № 1. – Р. 18
It is shown that adjustment of the temperature-rate modes of wheel heating and cooling in the range of working parameters of plasma equipment enables variation of the structural-phase condition of the surface, thus allowing microstructure optimization and providing high values of mechanical properties.
Grigorenko G. M., Golovko V. V., Kostin V. A. and Grabin V. F. Effect of microstructural factors on sensitivity of welds with ultra-low carbon content to brittle fracture // Paton Welding Journal. – 2005. – № 2. – Р. 2
Morphological features of microstructure of weld metal with ultra-low carbon content have been studied. It is shown that in such welds both MAC-phase and lamellar forms of ferrite are the structural factors that cause instability of properties. It has been found that the content of the MAC-phase should not exceed 5Ä6 vol.% at a low content of ferrite with an ordered secondary phase to provide consistently high properties at low temperatures. It is shown that impact toughness of the welds studied rises with increase in the content of the ductile component in fracture.
Ponomarev V. and Scotti A. Mechanism of long arc MIG/MAG welding metal transfer mixed modes provoked by inadequate dynamic features of the power source // Paton Welding Journal. – 2005. – № 3. – Р. 7
A mixed metal transfer mode in MIG/MAG welding, in which two or more transfer modes happen in a periodic sequence, is usually undesirable, because it may deteriorate the welding process stability. Thus, there is a strong appeal for investigating the causes of such a metal transfer mode in order to determine means of deal with this phenomenon. This work was aimed to make an experimental and descriptive analysis of the mechanisms that govern one of the free-flight metal transfer mixed mode in the MIG/MAG welding. For that, current rising and falling rates were systematically adjusted in an electronic power supply. The droplet formation and transfer were observed using an arc visualisation system based on a laser and a high-speed camera. The arc voltage and welding current signals were monitored, in synchronism with the droplet images (frames), using a computer-based measuring system. It was verified that one of the factors that provoke this mixed metal transfer mode is inadequate dynamic characteristics of the power source, namely, excessively fast current rising and falling rates that happen during welding circuit resistance changes caused by the metal droplet formation and detachment. The received results seem useful for electronic power source adjustments, as well as for designers of new welding power sources.
Arsenyuk V. V., Markashova L. I., Grigorenko G. M., Polovetsky E. V. and Bugaets V. P. Peculiarities of formation of structure of titanium-steel joints under explosion welding conditions // Paton Welding Journal. – 2005. – № 3. – Р. 19
Considered are principles of formation of structure and character of its variation in titanium-steel joints made by explosion welding, as well as factors provoking deterioration of properties of the joints.
Lebedev V. A. Mechanized cutting of metals with application of PSh107R semi-automatic machine // Paton Welding Journal. – 2005. – № 5. – Р. 36
The paper considers some features of practical use of the process of mechanized arc cutting of metals with application of a special semi-automatic machine of PSh107R type from the series of semi-automatic machines of a modular design. Several techniques and technologies are proposed that allow a significant increase of the speed of cutting and pulsed feed of the electrode wire.
Ryzhov R. N. and Kuznetsov V. D. Choice of optimal parameters of external electromagnetic action in arc methods of welding // Paton Welding Journal. – 2005. – № 6. – Р. 24
Dependencies are given which allow optimizing the parameters of electromagnetic action. Adequacy of the derived dependencies to the actual welding conditions is confirmed by comparative analysis of the calculated and experimental data. Analysis is performed of the influence of both the welding parameters and thermophysical properties of materials on the optimum range of the mode of electromagnetic action.
Ryzhov R. N. Application of combined electromagnetic actions for improving the quality of welds in welding with non-consumable electrode // Paton Welding Journal. – 2005. – № 7. – Р. 52
Experiments were the basis to conduct comparative analysis of the effectiveness of application of an electromagnetic impact with a pulsed axial and combined magnetic field to control the parameters of weld formation and solidification.
Korzh V. N. and Popil Yu. S. Producing a flame-sprayed coating using hydrogen-oxygen flame // Paton Welding Journal. – 2005. – № 9. – Р. 23
Influence of the combustible mixture composition and nature of its flow on the energy state of a spraying particle is considered. Conditions are established of producing flame-sprayed coatings of materials with different melting temperatures, using hydrogen-oxygen flame, generated when burning a mixture produced by water-electrolysis generators.
Lebedev V. A., Postolaty N. I. and Motry A. V. Multifunctional welding current source // Paton Welding Journal. – 2005. – № 9. – Р. 48
A multifunctional source is described, which is manufactured by Kakhovka Plant of Electric Welding Equipment for application in different processes of welding, surfacing, cutting, including use of acrotrons.
Labur T. M., Ishchenko A. Ya., Taranova T. G., Kostin V. A. and Grigorenko G. M. Nature and features of microdeformation in the zone of crack initiation and propagation in high-strength aluminuim alloy D16AT // Paton Welding Journal. – 2005. – № 10. – Р. 2
Features of microdeformation of individual structural components within the zone of crack initiation and propagation in a high-strength aluminium alloy have been studied. Characteristics of crack initiation and propagation have been determined. It is shown that a proportional relationship exists between the conditions of microdeformation of metal internal structure caused by initial stresses and the resistance to crack propagation.
Labur T. M., Ishchenko A. Ya., Taranova T. G., Kostin V. A. and Grigorenko G. M. Features of crack initiation and propagation under the conditions of off-center tension of 1441 AlÄLi alloy welded joints // Paton Welding Journal. – 2005. – № 11. – Р. 6
Peculiarities of initiation and propagation of cracks at fracture of metal in HAZ of welded joints on aluminium-lithium alloy 1441, depending upon the thermophysical conditions of welding and volume content of precipitating phases, have been studied. It is shown that formation of fracture centres is related to increase in the volume content of coarse phases present in the metal structure. It has been established that the rate of metal cooling in fusion welding affects the value of the energy of crack initiation in the alloy.
Ryzhov R. N., Maksimov S. Yu., Prilipko E. A. and Kozhukhar V. A. Influence of external electromagnetic actions on the structure and composition of welds in wet underwater welding // Paton Welding Journal. – 2005. – № 11. – Р. 34
Analysis of microstructures of all the welded joint zones and weld composition was the basis to determine the optimum parameters of the controlling magnetic field, providing maximum improvement of mechanical properties of the joints in wet underwater welding.