Irreversible thermodynamics of creep in crystalline solids

We develop an irreversible thermodynamics framework for the description of creep deformation in crystalline solids by mechanisms that involve vacancy diffusion and lattice site generation and annihilation. The material undergoing the creep deformation is treated as a non-hydrostatically stressed multi-component solid medium with non-conserved lattice sites and inhomogeneities handled by employing gradient thermodynamics. Phase fields describe microstructure evolution which gives rise to redistribution of vacancy sinks and sources in the material during the creep process. We derive a general expression for the entropy production rate and use it to identify of the relevant fluxes and driving forces and to formulate phenomenological relations among them taking into account symmetry properties of the material. As a simple application, we analyze a one-dimensional model of a bicrystal in which the grain boundary acts as a sink and source of vacancies. The kinetic equations of the model describe a creep deformation process accompanied by grain boundary migration and relative rigid translations of the grains. They also demonstrate the effect of grain boundary migration induced by a vacancy concentration gradient across the boundary

Main directions of production diversification and restructuring in the Russian Defence Industry Complex

The purpose of the article is to specify the proposals of the President of the Russian Federation on diversification and restructuring of production for the financial recovery of enterprises and organisations of the Russian Defence Industry Complex in terms of preparing proposals on procedures and tools for determining the optimal range of high-tech civilian products.The methodological basis of the approach proposed in the article is the specificity of the organisation of the production of defenсe products. The use of production and technological specialisation has been proposed as the main principle for developing a market organisational structure for managing a diversified defenсe enterprise.The comparative analysis of the specifics of military and civilian production's organisation have been carried out, and their fundamental differences have been revealed. The recommendations on the choice of optimal range of civilian products being mastered, have been given. The basic principles of building a market organisational structure for managing a diversified production and economic complex have been proposed. Based on this, a typical version of the structure has been presented.Diversification of modern production in the defence complex is a rather long-term labor-intensive and capital-intensive process. The proposals presented in the research paper will allow, especially at the initial stage of its implementation, to optimise the amount of state support through the correct choice of priority areas and projects for the production of high-tech civilian products, and the transition to a new organisational structure. All this will contribute to saving limited budgetary funds and to carrying out the necessary organisational and structural changes in the industry