The behavior of metals in both low-cycle (LCF) and high-cycle fatigue (HCF) regimes is considered using Ni-based (grade EI698) and Ti-based (grade VT22) alloys. It is shown that the mechanism characterizing the crack ...
The behavior of metals in both low-cycle (LCF) and high-cycle fatigue (HCF) regimes is considered using Ni-based (grade EI698) and Ti-based (grade VT22) alloys. It is shown that the mechanism characterizing the crack initiation in the LCF regime by persistent slip band formation does not correspond to the crack initiation mechanism in the HCF one. Data on the relationship between the yield stress and the fatigue limit of structural materials are generalized and it is revealed that in more than 95 % of metals, the fatigue limit is lower than the yield stress. The regularities of the evolution of hysteresis loops in the EI986 alloy with an increase in the number of loading cycles when fracture occurs under LCF regime are shown, and the absence of hysteresis loops in the VT22 alloy, fractured under HCF regime, is shown at the approximately similar number of cycles. The regularities of fracture relief formation in both alloys are studied, and kinetic curves are plotted by using the measured fatigue striation spacings. A generalized fatigue failure diagram is demonstrated, which, at a ratio of σ –1 /σ 0.2 ≥ 1, coincides with the previously proposed by Mughrabi, which explains the nature of the subsurface fracture origin formation.
We consider the hypersonic CO2 flow field around a spaceship in the Martian atmosphere using different models of multi-component diffusion. Transport coefficients of a multi-component gas mixture determined in accorda...
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To simplify the calculations of flow about wing with different possible deflections of aerodynamic surfaces, the algorithm with linearization of a boundary condition of impermeability is offered and implemented. The s...
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The flow of an incompressible Newtonian fluid with a free boundary in contact with air is considered. In this paper, there will be problems with a flat bottom for different initial and boundary conditions. The choice ...
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In this article the results of series of works concerning free-surface flows in liquid medium. Two models were considered: Free-surface flows of homogeneous liquid and flows in density stratified liquid. For first mod...
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The development of fundamental ideas about the inelastic deformation and fracture of materials is of great practical importance. This is substantiated by the need for a macroscopic theory suitable for solving engineer...
The development of fundamental ideas about the inelastic deformation and fracture of materials is of great practical importance. This is substantiated by the need for a macroscopic theory suitable for solving engineering problems and taking into account real physical processes occurring in a deformed material. Such a theory can be efficiently used in problems of computer-aideddesign of materials with required mechanical properties. This paper is devoted to the formulation of the principles of the macroscopic theory of inelastic deformation, which couples the mechanical and physical aspects. The theory combines two macroscopic theories: the classical theory of elasticity and the continuum theory of translational defects. The proposed theory uses the Lagrangian formalism in combination with the gauge field method. The latter allows introducing defects of the translational type. The application of the principle of least action to the Lagrangian with gauge fields made it possible to obtain the equations of motion for both elastic displacements and defects. The adequacy of the proposed theory is confirmed by several classical examples.
The paper studies a building-up process where low-velocity heated micro-particles collide with an undeformed substrate. For a model of a one-dimensional rigid plastic collision with the law of hardening close to linea...
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Continual models of solid media with a discrete set of slip planes (layered, block media) and with nonlinear type slip conditions at the contact boundaries of structural elements are constructed. The constitutive equa...
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Abstract: The properties of the dynamics of a single massive particle and a system of massive particles are considered in the Kruskal metric, which is the maximal analytical extension of the Hilbert metric to a gravit...
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In the article it is shown that the process of digitalization of the information society, which is now a trend of world development, should be considered in the context of consumer, management and technological aspect...
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