|
PATON B.E. Space technologies on the threshold of the third millenium |
2 |
| Promising trends in development of space technologies in the next decades are discussed. Special attention is given to comprehensive material science research. | |
|
ISHCHENKO A.Ya. and
CHAPOR V.O. Weldability of high-strength alloys of Al-Zn-Mg-(Cu) system (Review) |
5 |
| The problems of welding high-strength alloys of Al-Zn-Mg-(Cu) system are considered. The effect of chemical composition of alloys and filler material on the weldability characteristics is analyzed. Causes of defect formation in the welded joint are described. The problems of weldability and degree of metal weakening under the action of a thermal cycle depending on the method of welding are outlined. The further investigations for improving weldability of alloys of Al-Zn-Mg and Al-Zn-Mg-(Cu) systems are predicted. | |
|
RAZMYSHLYAEV A.D. Control of bead formation in arc surfacing with strip electrode |
11 |
| Electromagnetic nature of a defect in the weld bead in the form of a cavity (saddle) formed in its central portion in DC submerged-arc surfacing using strip electrode is described. It is suggested that the controlling magnetic fields should be used to compensate for asymmetry of the magnetic field induced in the arc zone by the surfacing current flowing through the strip electrode extension. | |
|
BOLOTOV G.P. Peculiarities of heating parts of limited sizes in glow-discharge diffusion bonding |
15 |
| Character of distribution of heat flows in parts of limited sizes in glow-discharge heating under conditions of diffusion bonding is analysed. The expediency of using heat-insulating spacers between a part and a clamp is shown. The precise and approximate solutions of the problem of temperature distribution in parts, depending upon thermal-physical and geometrical characteristics of base materials and spacers, are given. | |
| Pilot Plant for Welding Consumables today | 19 |
|
RYABTSEV I.A., KUSKOV
Yu.M. and CHERNYAK Ya.P. Formation of deposited metal on inclined and vertical surfaces |
22 |
| The effect of surfacing conditions, compositions of charges of flux-cored wires and fluxes on the formation of a horizontal bead on inclined and vertical surfaces is experimentally investigated. It is shown that deposition on such surfaces should be done at a minimum possible amperage and maximum speed. The best choice for surfacing is the short flux of the AN-15M grade. The CaCO3-CaF2-TiO2 gas-slag forming system with a component ratio of 3:1:1 provides the best results in the manufacture of self-shielded flux-cored wire. | |
|
DMITRIK V.V. Structure of welded joints from low-alloyed heat-resistant Cr-Mo-V pearlitic steels |
26 |
| Peculiarities of technology of CO2 automatic welding of structures from heat-resistant Cr-Mo-V pearlitic steels are considered. Technology is based on the results of modelling of temperature conditions of the welding process and provides structure in welded joints which is close to optimum. | |
|
NESTERENKO N.P. Features of the technology of ultrasonic welding of axially symmetrical polyethylene containers |
30 |
| The influence of modes of ultrasonic welding and methods of introducing mechanical vibrations into the weld zone on the quality of welded joints produced in sealing of polyethylene containers is considered. It is shown that with the decrease of the static compression force in the forging stage and of welding time the welded joint quality is improved at the expense of a more uniform morphology, absence of defects or texture in the weld zone. A new welding cycle and the appropriate schematic of dosing the energy of the introduced mechanical vibrations are proposed. Recommendations are issued on industrial use of the developed technology. | |
|
LEBEDEV V.A. and
PICHAK V.G. A new approach to design of the electrode wire feed mechanism
P. 33
MIKHED A.M. and
CHERNYSH V.P. Restoration of the dimensions and properties of cast iron cylindrical parts by resistance build-up welding with wire |
33 |
| The reduction gear mechanisms of electrode wire feed with roller motors, widely used in mechanized arc welding equipment, are analyzed. It is shown that with the increase of the feed roller diameter the values of tractive characteristics of the mechanism become higher, service life is extended and losses in the roller feed unit are reduced. A design of the feed roller is given characterized by a unrestrained mounting of the feeding element on the driving element. This provides the invariance of the electrode wire feed rate to its diameter, fast mounting and dismantling of the feed roller in the case of its replacement. | |
|
LUKASH E.S., SHULYM
V.F., GRIGORENKO G.M., SMIYAN O.D. and NEZNAMOVA L.O. Investigation of the influence of gravity on the composition of coatings from binary Ag-Cu alloys |
37 |
| The method of Auger-spectroscopy was used to study the composition of coatings of Al-Cu alloys produced under different gravity conditions. Some features of formation of coatings from binary alloys under zero gravity are considered. The results of metallographic investigations of the structure of the alloys remnants after evaporation in space and on the Earth are given. | |
|
TUGOLUKOV A.V., KLYUCHNIK
O.N. and BUDYUK E.D. Structure of martensitic-ferritic steels after surface plasma hardening |
41 |
| Surface plasma treatment provides a fundamental increase in hardness of steel 20Kh17N2. This is achieved by varying power of the plasma jet and increasing its concentration. Metallography revealed three characteristic regions formed as a result of the plasma jet effect. An increase in the concentration of the heat flow affecting the sample surface causes a decrease in the hardened and transition zones, decrease in the amount of carbides in the bulk of the main phases and reduction in grain size | |
|
BERESTOVOY A.M. Dimensions of the zone of boiler walls cleaning from solidified pitch in welding up cracks |
45 |
| Sizes of the zones to be cleaned from pitch for repair welding of cracks formed during operation in the tank boilers were established experimentally using simulation samples. The possibility of avoiding overall cleaning of the tank boiler is proved. The technology for repair welding of cracks eliminating inflammation of pitch is described. | |
|
KOVALYOV V.D., VASHCHENKO
N.M. and TARASENKO A.G. Portable mechanical devices for cutting and preparation of pipes for welding |
47 |
| Pneumatic portable metal-cutting machine-tools for cutting pipes of diameter from 20 to 1220 mm in site and pipe facing for welding are described. Portable pipe cutting and facing machines can be used in manufacture and repair of pipelines. Unique designs of captive non-detachable pipe cutters are given. | |
| ADVERTISING | 50 |