Chelyabinsk Physical and Mathematical Journal最新文献

ESTIMATION OF DYNAMIC YIELD STRESS BY TAYLOR TEST WITH REDUCED CYLINDRICAL HEAD PART OF SAMPLES 用Taylor试验估计样品的动态屈服应力

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-399-409

E.S. Rodionov, A.E. Mayer

{"title":"ESTIMATION OF DYNAMIC YIELD STRESS BY TAYLOR TEST WITH REDUCED CYLINDRICAL HEAD PART OF SAMPLES","authors":"E.S. Rodionov, A.E. Mayer","doi":"10.47475/2500-0101-2023-8-3-399-409","DOIUrl":"https://doi.org/10.47475/2500-0101-2023-8-3-399-409","url":null,"abstract":"A simple method is proposed to estimate the dynamic yield stress of materials using modified Taylor tests for high-velocity impact of profiled cylinders with a reduced diameter of the head part. Assuming the uniformity of deformations and stresses in the head part, formulas are derived for estimating the yield stress and strain rate from the change in the length of the reduced head part, as well as the mass of the sample and the impact velocity. This estimation is verified by comparison with the results of numerical calculations by the SPH method based on the dislocation plasticity model parameterized for cold-rolled oxygen-free copper. It is shown that the stopping time of the sample and the strain rate are reproduced with good accuracy, and the shear strength estimate gives an error that increases with the impact velocity. At velocities that do not lead to deformation of a wide part of the sample (up to 90 m/s in the case under consideration), the error increases linearly up to 30%, which can be taken into account by a correction factor. The proposed estimate, taking into account the correction factor, was applied to analyze the results of previous experiments; the obtained values correspond to the literature data on the rate dependence of the shear strength.","PeriodicalId":36654,"journal":{"name":"Chelyabinsk Physical and Mathematical Journal","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135209403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

REFINEMENT OF MACINTYRE - EVGRAFOV TYPE THEOREMS 机器- evgrafov型定理的改进

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-309-318

A.M. Gaisin, G.A. Gaisina

{"title":"REFINEMENT OF MACINTYRE - EVGRAFOV TYPE THEOREMS","authors":"A.M. Gaisin, G.A. Gaisina","doi":"10.47475/2500-0101-2023-8-3-309-318","DOIUrl":"https://doi.org/10.47475/2500-0101-2023-8-3-309-318","url":null,"abstract":"The study of the asymptotic behavior of an entire transcendental function of the form f(z) = Pn anzpn, pn ∈ N, on curves γ going to infinity arbitrarily, is a classical problem, goes back to the works of Hadamard, Littlewood and Polia. Polia posed the following problem: under what conditions on pn does there unbounded sequence {ξn} ⊂ γ exist such that lnMf(|ξn|) ∼ ln|f(ξn)| for ξn → ∞ (Polya’s problem). Here Mf(r) is the maximum of the modulus f on a circle of radius r. He showed that if the sequence {pn} has zero density and f is of finite order, then the indicated relation between lnMf(|ξn|) and ln|f(ξn)| is always present. This assertion is also true in the case when f has a finite lower order: the final results for this case were obtained by A.M.Gaisin, I.D.Latypov and N.N.Yusupova-Aitkuzhina. We consider the situation when the lower order is equal to infinity. A.M. Gaisin received an answer to Polia’s problem in 2003. This is the criterion. If the conditions of this criterion are satisfied not by the sequence {pn} itself, but only by a subsequence — a sequence of central exponents, then the logarithms of the maximum modulus and modulus of the sum of the series will also be equivalent in the indicated sense on any curve γ going to infinity.","PeriodicalId":36654,"journal":{"name":"Chelyabinsk Physical and Mathematical Journal","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135208316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

STUDY OF THE TEMPERATURE DEPENDENCE OF THE SYMMETRICAL GRAIN BOUNDARY ENERGIES ON THE PLANE (110) IN ALUMINUM 铝平面(110)上对称晶界能温度依赖性的研究

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-421-435

E.V. Fomin

{"title":"STUDY OF THE TEMPERATURE DEPENDENCE OF THE SYMMETRICAL GRAIN BOUNDARY ENERGIES ON THE PLANE (110) IN ALUMINUM","authors":"E.V. Fomin","doi":"10.47475/2500-0101-2023-8-3-421-435","DOIUrl":"https://doi.org/10.47475/2500-0101-2023-8-3-421-435","url":null,"abstract":"In this work the energy of symmetric tilt and twist grain boundaries in the range of grain misorientation angles from 0 to 180◦ and temperatures from 100 to 700 K in pure aluminum is investigated. The bicrystal systems with different grain tilt/twist angles are maintained at constant temperatures of 100, 400, or 700 K by molecular dynamic method and the energy of each grain boundary is calculated. The results show that the minimum grain boundary energy decreases as the temperature increases from 100 to 400 K; but the energy may decrease, remain practically unchanged, or even increase with further heating to 700 K. The average grain boundary energy obtained by averaging the energies of the resulting grain boundary structure variations at constant temperature grows with increasing temperature from 100 to 700 K for random boundaries with initially high energies. In the case of special grain boundaries with small Σ values, the average energy will be practically unchanged. To describe the continuous energy dependence of symmetric tilt and twist boundaries on temperature, an approximation by an forward propagation of artificial neural network is proposed. The neural network is trained and tested on atomistic simulation data and shows high predictive ability on test data and to describe the boundary energy in the temperature range from 100 to 700 K.","PeriodicalId":36654,"journal":{"name":"Chelyabinsk Physical and Mathematical Journal","volume":"193 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135209696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

STUDY OF EXTRAORDINARY PHASE TRANSITION IN THIN ANTI-FERROMAGNETIC FILMS: COMPUTER SIMULATION 反铁磁薄膜中异常相变的研究:计算机模拟

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-410-420

S.V. Belim, E.V. Bogdanova

引用次数: 0

HISTORY OF THE DISSERTATION COUNCIL 24.2.431.01 (Ä 212.296.03) (2012–2022) 论文委员会历史24.2.431.01 (Ä 212.296.03) (2012-2022)

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-436-457

M.A. Zagrebin, V.D. Buchelnikov

引用次数: 0

BOUNDARY VALUE PROBLEM FOR THE EQUATION OF UNSTEADY THERMAL CONDUCTIVITY IN A NON-CYLINDRICAL REGION 非圆柱形区域非定常导热方程的边值问题

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-319-330

R.G. Zainullin, Z.Yu. Fazullin

{"title":"BOUNDARY VALUE PROBLEM FOR THE EQUATION OF UNSTEADY THERMAL CONDUCTIVITY IN A NON-CYLINDRICAL REGION","authors":"R.G. Zainullin, Z.Yu. Fazullin","doi":"10.47475/2500-0101-2023-8-3-319-330","DOIUrl":"https://doi.org/10.47475/2500-0101-2023-8-3-319-330","url":null,"abstract":"The application of the method of decomposition by eigenfunctions of a self-adjoint differential operator to solving a non-stationary heat transfer problem with a phase transition in a non-automatic formulation under special initial conditions is presented for the example of the solidification process in a continuous medium. The one-dimensional problem is solved in spherical coordinates. Solving of the problem begins with its transformation to a problem in a domain with fixed boundaries, then a finite integral transformation with an unknown kernel is constructed to solve the transformed problem, the finding of which is associated with the formulation and solving of the corresponding spectral problem through degenerate hypergeometric functions. The eigenvalues and eigenfunctions are found, as well as the inversion formula for the introduced integral transformation, which makes it possible to write out an analytical solution to the problem. In the course of solving the problem, the parabolic law of motion of the interface of the two phases is established. Problems of this type arise in the mathematical modeling of heat transfer processes in construction, especially in permafrost areas, in oil and gas production during drilling and operation of wells, in metallurgy, etc.","PeriodicalId":36654,"journal":{"name":"Chelyabinsk Physical and Mathematical Journal","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135208314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

RECOVERING OF THE HEAT TRANSFER COEFFICIENT IN TRANSMISSION PROBLEMS WITH IMPERFECT CONTACT CONDITIONS 不完全接触条件下传热问题传热系数的恢复

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-331-350

S.G. Pyatkov, V.A. Belonogov

引用次数: 0

BOUNDARY VALUE PROBLEM FOR THE EQUATION OF UNSTEADY THERMAL CONDUCTIVITY IN A NON-CYLINDRICAL REGION 非圆柱形区域非定常导热方程的边值问题

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/10.47475/2500-0101-2023-8-3-319-330

R.G. Zainullin, Z.Yu. Fazullin

{"title":"BOUNDARY VALUE PROBLEM FOR THE EQUATION OF UNSTEADY THERMAL CONDUCTIVITY IN A NON-CYLINDRICAL REGION","authors":"R.G. Zainullin, Z.Yu. Fazullin","doi":"10.47475/10.47475/2500-0101-2023-8-3-319-330","DOIUrl":"https://doi.org/10.47475/10.47475/2500-0101-2023-8-3-319-330","url":null,"abstract":"The application of the method of decomposition by eigenfunctions of a self-adjoint differential operator to solving a non-stationary heat transfer problem with a phase transition in a non-automatic formulation under special initial conditions is presented for the example of the solidification process in a continuous medium. The one-dimensional problem is solved in spherical coordinates. Solving of the problem begins with its transformation to a problem in a domain with fixed boundaries, then a finite integral transformation with an unknown kernel is constructed to solve the transformed problem, the finding of which is associated with the formulation and solving of the corresponding spectral problem through degenerate hypergeometric functions. The eigenvalues and eigenfunctions are found, as well as the inversion formula for the introduced integral transformation, which makes it possible to write out an analytical solution to the problem. In the course of solving the problem, the parabolic law of motion of the interface of the two phases is established. Problems of this type arise in the mathematical modeling of heat transfer processes in construction, especially in permafrost areas, in oil and gas production during drilling and operation of wells, in metallurgy, etc.","PeriodicalId":36654,"journal":{"name":"Chelyabinsk Physical and Mathematical Journal","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135208318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

UNIQUE SOLVABILITY OF IBVP FOR PSEUDO-SUBDIFFUSION EQUATION WITH HILFER FRACTIONAL DERIVATIVE ON A METRIC GRAPH 度量图上具有分数阶导数的伪次扩散方程的ibvp的唯一可解性

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-351-370

Z.A. Sobirov, J.R. Khujakulov, A.A. Turemuratova

引用次数: 0

DYNAMICS OF THE PLOW’S WORKING BODY UNDER THE ACTION OF VIBRATIONS 在振动作用下犁体的动力学

Chelyabinsk Physical and Mathematical Journal Pub Date : 2023-09-18 DOI: 10.47475/2500-0101-2023-8-3-387-398

A.R. Yalaletdinov, I.R. Rahimov, A.P. Kulikova, I.V. Bychkov, D.A. Kuzmin, D.A. Yalaletdinov, M.O. Usik, V.A. Tolkachev

引用次数: 0