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The rapid economic development of territories of the Arctic and Siberia is directly associated with the development of new technologies in science of materials, design and production of technical systems by scientists and designers which can function successfully at low temperatures. These problems were on the agenda of the 2nd Eurasian symposium held on the initiative of Ministries of education, science, industry and energy of the Russian Federation, RAS, other Russian and foreign organizations in the city of Yakutsk at the end of 2004. The symposium agenda included 22 plenary meetings, 114 sections and 53 stand displays.
The issues under consideration largely dealt with increasing the reliability of northern and Siberian pipelines, ensurance of their efficiency and safety.
Many speakers underlined that nowadays it was necessary to use on a broader scale technical structures made of polymer and composite materials whose main advantage is low specific weight. Today they constitute one third of all materials available on the markets of developed countries and in Russia this share is less than 7 percent.
It was pointed out in particular that economists of the Sakha Republic have accumulated the greatest experience in this regard. It was in Sakha where for the first time large-scale experiments had been held to study mechanical interactions of polyethylene pipes with permafrost ground which showed the fundamental possibility and advantages of employing them in pipelines construction in the respective regions.
In the course of discussions the key requirements for metal, polymer and compound materials have been identified. These are stability of the characteristics in long operation at low temperatures, low cost of production, low energy consumption in manufacturing processes and bionomics.
Yet, so far metal remains the most common construction raw material. The symposium has named a new generation of cold-resistant steels, alloyed by vanadium, niobium and other rare-earth elements. Such products inherit unique strength, high resistance to brittle and fatigue damage.
Among the promising methods of metal structural formation the most interesting is the production of superfine grain conditions by intense plastic deformation i.e. by equal-channel angular pressing.
Non-equilibrium physical processes (shock-wave, plasma, gas-thermal) which are used in a broad range of temperatures and rates of changes of the volume and shape of products offer broad for developing high-strength cold-resistant and durable materials. Some reports considered such new lines of studies as physical mesomechanics and synergetics.
It was underlined at the symposium that the requirements for the expected service life, viability and safety of products have been growing in recent years. Thus, today when analyzing some or other engineering structures the minimum accepted operating temperature is -40°C although, in reality the temperature may reach -55°C, and according to world standards the temperature must not be below -100°C, which, naturally,
makes Russian scientists to further search for effective solutions.
The strengthening of technical systems doesn't only imply the development of new materials but also advanced methods of production of some or others structures. Here, as we know, the main role belongs to welding. Machines' reliability and long service life depend on the quality of welding. In fact the destruction analysis of products which have been employed at low temperatures shows that most failures occur at welding joints or start within them. Presented at the symposium were effective technologies of the necessary processes i. e. adaptive pulse ark welding and method of additional processing (thermal cycling, shock-wave stressing and etc.); alloying a joint material by welding; control of hydrogen behavior in welded joints and etc.
A number of speakers underlined that the major trend in increasing the reliability of equipment and gear in cold zones remains the formation of special surface coating of structures in order to increase the strength of components under contact loads. One of the most promising methods of production of wear-proof surfaces is plasma and gas-thermal powder coating. The possibilities of applying these methods are associated with the specifics of basic physical processes: high temperature, high activity of applied particles and energy concentration.
The symposium participants made recommendations on ways of ensuring the reliable operation of technical structures in low temperatures and permafrost including the development of the systematic approach conception for solving this problem at all stages of service life, including design, production and use of machinery and mechanisms, creating data base of physical, chemical and technological properties of specific materials; development of new approaches to improving surface coating of technical structures which are in operation in regions with extreme climate; perfection of progressive technologies for reprocessing multycomponent mineral raw materials and industrial diamonds.
The Yakutsk forum adopted the documents for coordinating the activities ensuring the development and implementation of expensive Hi-Tech innovations. In order to achieve this goal it is necessary to bring back to life the federal target program "The Technology of the Russian North" providing for design, testing, and mass production of new cold-resistant materials and machines in the northern versions, and of mining and transport mechanical equipment, autonomous life-support systems.
Nauka v Sibiri, (Science in Siberia), 2004
Prepared by Yaroslav RENKAS
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