Hardening kinetics of the stress-strain state of a cylinder made of steel 45

1996 ◽  
Vol 38 (9) ◽  
pp. 399-403
Author(s):  
N. I. Zagryatskii ◽  
T. P. Vinogradova
2021 ◽  
Vol 2021 (1) ◽  
pp. 2-6
Author(s):  
O.V. Makhnenko ◽  
◽  
O.S. Milenin ◽  
O.A. Velykoivanenko ◽  
G.P. Rozynka ◽  
...  

1989 ◽  
Vol 21 (1) ◽  
pp. 74-80
Author(s):  
A. V. Yakimov ◽  
V. S. Morganyuk ◽  
I. P. Sazonov

Author(s):  
L. M. Gurevich ◽  
V. F. Danenko ◽  
S. P. Pisarev ◽  
V. Abo-Shakra ◽  
D. V. Shagoyan

The influence of the dimensions of the punch of a step-forming press on the stress-strain state in a pipe billet of longitudinal welded pipes of large diameter has been studied by the methods of finite element simulate. Pipes are made of steel X70. The kinetics of changes in the magnitude of deformations and stresses during one step of forming has been determined.


2021 ◽  
Vol 263 ◽  
pp. 03009
Author(s):  
Ilya Ovchinnikov ◽  
Vladimir Avzovin

Quite a lot of works have been devoted to the problem of modeling the behavior of thin-walled structures exposed to an aggressive environment leading to corrosive wear of their surface. Researchers have proposed a fairly large set of models of corrosive wear, taking into account the influence of various factors on the kinetics of corrosion (time, material, temperature, the nature of the corrosive environment, the stress-strain state of the structure). Moreover, different authors often propose different models for the same conditions. In the article under consideration, a rather unique comparative study of three corrosion models proposed by different authors (Dolinsky V.M., Gutman E.M., Ovchinnikov I.G.) was carried out to simulate the behavior of the same circular plate subjected to the combined action of load and corrosion wear and tear. Moreover, the identification of the models, that is, the determination of the coefficients included in them, was carried out using the same experimental data. These models were then used to simulate the behavior of plates subject to corrosive wear under various loads. The results of numerical simulation were compared with experimental data obtained during testing of corrosive plates. Interestingly, in the models used, the effect of the stress state on the kinetics of corrosion was taken into account using different invariants of the stress state: the stress intensity in V.M. Dolinsky, medium voltage in the model of E.M. Gutman, and the specific energy in the model of I.G. Ovchinnikov. The analysis showed that the difference from the experiment when using the three models considered does not exceed 9.3%. The discrepancy between the results obtained using different models is also within the acceptable range, which suggests that all three models can be used to predict the behavior of plates under corrosive wear conditions. However, it is of interest to conduct research on the predictive capabilities of models on large forecast arms that go beyond the scope of experimental studies. At the same time, carrying out numerical experiments to simulate the behavior of complex structures in a stressed state and subject to corrosive wear, using several models that allow a good description of the experimental data and the most complete consideration of the operating conditions, makes it possible to obtain a more complete and versatile picture of what is happening in design processes, in comparison with the calculations performed according to one model, even if it describes the experimental data well.


Author(s):  
L. M. Gurevich ◽  
V. F. Danenko ◽  
S. P. Pisarev

The stress-strain state in a pipe billet of longitudinal seam pipes of large diameter made of X70 steel has been studied by the methods of finite element modeling under various technological parameters. The kinetics of the change in the deformation force and reactions of the supports during one step of molding have been determined.


2021 ◽  
Vol 2021 (1) ◽  
pp. 3-8
Author(s):  
O.V. Makhenko ◽  
◽  
O.S. Milenin ◽  
O.A. Velikoivanenko ◽  
G.P. Rozynka ◽  
...  

2019 ◽  
Vol 85 (2) ◽  
pp. 42-47
Author(s):  
A. A. Bautin ◽  
Yu. A. Svirsky ◽  
A. V. Pankov

The paper describes one of the most promising ways of structure health monitoring based on analysis of the kinetics of local stress-strain state. Comparison with other methods of damage detection and advantages of the stress-strain state control are considered. To implement this method of monitoring, two types of sensors are considered: strain gauges and fiber Bragg gratings (FBG). The advantages of FBG, due to which their use in operation is most preferable, are presented. The possibility of using stress-strain state control is analyzed for a promising transport aircraft using the results of tensometry under cyclic loading. The relevance of the work is confirmed by various examples of using monitoring methods in on-board systems during operation. The possibility of monitoring the airframe parts is demonstrated for longitudinal fuselage joints as an example. The change in the stress-strain state of the longitudinal joints, caused by structural damage was confirmed by tensometry analysis and by analysis of the stress-strain state of bearing sheet by the finite element method (FEM), taking into account the fatigue cracks originated during cyclic loading. The results of the calculation are compared with the tensometry data. Proceeding from the results of the calculation of the stress-strain state of the damaged and undamaged structure, the zones of the greatest deformation change are determined to optimize potential locations for the sensors. The optimal placing of the sensors for monitoring the integrity of the joints is proposed. The study confirms that the method of damage monitoring of the structure, developed on the basis of changes in the kinetics of the stress-strain state, can be successfully used in tests for maintaining the integrity of joints and other places with multi-site damages, where the methods of visual and non-destructive testing are not effective.


Author(s):  
А. Г. Гребеников ◽  
И. В. Малков ◽  
В. А. Урбанович ◽  
Н. И. Москаленко ◽  
Д. С. Колодийчик

The analysis of the design and technological features of the tail boom (ТB) of a helicopter made of polymer composite materials (PCM) is carried out.Three structural and technological concepts are distinguished - semi-monocoque (reinforced metal structure), monocoque (three-layer structure) and mesh-type structure. The high weight and economic efficiency of mesh structures is shown, which allows them to be used in aerospace engineering. The physicomechanical characteristics of the network structures are estimated and their uniqueness is shown. The use of mesh structures can reduce the weight of the product by a factor of two or more.The stress-strain state (SSS) of the proposed tail boom design is determined. The analysis of methods for calculating the characteristics of the total SSS of conical mesh shells is carried out. The design of the tail boom is presented, the design diagram of the tail boom of the transport category rotorcraft is developed. A finite element model was created using the Siemens NX 7.5 system. The calculation of the stress-strain state (SSS) of the HC of the helicopter was carried out on the basis of the developed structural scheme using the Advanced Simulation module of the Siemens NX 7.5 system. The main zones of probable fatigue failure of tail booms are determined. Finite Element Analysis (FEA) provides a theoretical basis for design decisions.Shown is the effect of the type of technological process selected for the production of the tail boom on the strength of the HB structure. The stability of the characteristics of the PCM tail boom largely depends on the extent to which its design is suitable for the use of mechanized and automated production processes.A method for the manufacture of a helicopter tail boom from PCM by the automated winding method is proposed. A variant of computer modeling of the tail boom of a mesh structure made of PCM is shown.The automated winding technology can be recommended for implementation in the design of the composite tail boom of the Mi-2 and Mi-8 helicopters.


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