3 research outputs found
Estimation of Temperature Conductivity Coefficient Impact upon Fatigue Damage of Material
In the paper we consider the peculiarities of adhesive wear of cutting tools. Simulation of heat flows in the cutting zone showed that, as thermal conduction and heat conductivity of tool material grow, the heat flows from the front and back surfaces to tool holder will increase and so, the temperature of the contact areas of the tool will lower. When estimating the adhesive wear rate of cemented-carbide tool under the cutting rates corresponding to the cutting temperature of up to 900 °С, it is necessary to take the fatigue character of adhesive wear into consideration. The process of accumulation and development of fatigue damage is associated with micro- and macroplastic flowing of material, which is determined by the processes of initiation, motion, generation, and elimination of line defects - dislocations. Density of dislocations grows with increase of the loading cycles amount and increase of load amplitude. Growth of dislocations density leads to loosening of material, formation of micro- and macrocracks. The heat capacity of material grows as the loosening continues. In the given paper the authors prove theoretically that temperature conductivity coefficient which is associated with heat capacity of material, decreases as fatigue wear grows
Calculation of the Intensity of Adhesive-Fatigue Wear of Cutting Tools
On the base of kinetic equation of strength the authors suggest the method carbide tools wear intensity calculation allowing comparing wear resistance basing on tool material thermal diffusivity coefficient. The authors obtain equations of tool wear resistance dependences upon its thermal diffusivity which show close correlation between these parameters. The results of wear intensity calculations correspond well to the experimental results under the cutting rates corresponding to the region of adhesive-fatigue wear. The inserts with low thermal diffusivity coefficient are characterized by lower wear rate at the inial and normal stages of wear
ПРИКЛАДНОЙ БАКАЛАВРИАТ КАК СТУПЕНЬ НЕПРЕРЫВНОГО ТЕХНИЧЕСКОГО ОБРАЗОВАНИЯ
The paper presents the most important research findings on the issue of lifelong learning strategy in Russia and some economically developed countries of the world. The term lifelong learning is not new. In the Soviet Union there were schools of extended studies for top officials and specialists, and in-plant training courses for workers. In the USA, as well as in Great Britain, France, Germany and some other countries qualified workers are trained within the system of two, five or even more year’s apprenticeship. There is also a net of national, public and private schools and in-plant training courses for adults. Russian educators mean education level continuation (from basic through secondary to higher vocational education), when talking about lifelong learning. The 2020 Long-term Social and Economic Development Strategy of the Russian Federation demands development of the high-tech sector of economy, alongside with creation of high-tech working places for new skilled specialists. Qualified specialists might be trained through the new programs of applied baccalaureate that guarantee practice-based training. A model of an integrated practice-based applied baccalaureate training program, which is currently being realized at Yurga Institute of Technology (affiliated) National Research Tomsk Polytechnic University, is specified.В статье рассмотрены аспекты развития непрерывного образования в нашей стране и за рубежом. Термин непрерывного образования не является новым. В советское время предусматривалось непрерывное обучение руководящих работников и специалистов и непрерывное обучение рабочих. В США, Великобритании, Франции, Германии и других странах получила развитие профессиональная подготовка квалифицированных рабочих в системе ученичества со сроком обучения от 2 до 5, а иногда и более лет, существует сеть государственных, общественных и частных школ, курсов для профессионального обучения взрослых без отрыва от работы. В российской традиции термин непрерывное образование обычно означает преемственность различных уровней образования: начального, среднего и высшего. Концепцией долгосрочного социально-экономического развития РФ до 2020 года предусмотрено развитие высокотехнологичных секторов экономики и создание высокотехнологичных рабочих мест, требующих особых компетенций специалистов. Подготовку таких специалистов должно обеспечить новое направление обучения специалистов – прикладной бакалавриат. Прикладной бакалавриат обеспечивает профессиональную практико-ориентированную подготовку. Представлена модель реализации прикладного бакалавриата на базе интегрированной системы подготовки специалистов, реализуемой в Юргинском технологическом институте Томского политехнического университета, позволяющая готовить практико-ориентированных специалистов