KSHP. OMD №9-2019

S. I. Feoktistov, Zho Zayar So (Komsomolsk-na-Amure State University, Komsomolsk-on-Amur)

Determination of the limiting expanding ratio by FLD-diagrams

The paper describes a method which has been developed for obtaining the limiting expansion ratio and determines the moment of failure of the workpiece. This method is based on not only the use of Forming Limit Diagram (FLD) in predicting the failure of the blank, but also the using method of variable parameters of elasticity in determining the stress-strain state in expansion process.
Keywords: FLD-diagram; forming limit diagram; expanding; method of variable parameters of elasticity; technological capabilities.

N. L. Lisuneс, KHOANG MAN' ZHOY (National University of Science and Technology «MISIS», Moscow)

Investigation of the force regime of closed stamping by transverse draft and extrusion in a rectangular matrix

Now in the Metalworking industry the priority direction is introduction of the resource-saving technologies providing economy of materials and decrease in labor input due to reduction of number of technological operations. In this paper, the power mode of the closed transverse precipitation of the bar billet in a rectangular matrix is studied and the possibility of combining it with the operation of stamping by extrusion in one die is studied.
Keywords: rod billet; rectangular matrix; a closed transverse sediment squeezing; the contact of the power fuse; simulation model.

A. S. Chumadin (Moscow Aviation Institute (National Research University), Moscow)

Method of manufacturing thin-walled parts such as a body with a wide flange

The article proposes a new method of manufacturing parts like a body with a wide flange. The process of rotary processing is used. The results of experimental studies are presented.
Keywords: method of manufacturing; a body with a wide flange; the process of rotary processing; experiment.

V. A. Glushchenkov, I. A. Belyaeva, A. M. Pyl'tsyn (Samara National Research University named after Academician S. P. Korolev, Samara)

Tool stamp with technology of drawing-trimming allowance

The article presents the design of a tool stamp, which allows implementing the combined technology of drawing-trimming allowance combining static and dynamic loading. As a dynamic load, a pulsed magnetic field is used. Structural features of the stamp were an inductor integrated into the punch connected to a magnetic pulse installation and a composite exhaust matrix with cutting edges.
Keywords: tool stamp; combined technology; extractor hood; trimming allowance; static and magnetic pulse loads; inductor.

E. N. Sosenushkin, E. A. Yanovskaya, A. E. Sosenushkin (MSTU «STANKIN», Moscow)

Analytical and physical models of reverse extrusion technology

The issues of design and implementation of the processes of bulk forming hollow glasses with a bottom are considered. From the variety of technological processes, it is necessary to choose options with a smaller number of punching transitions and, if possible, with minimal specific forces and moderate degrees of deformation. Decision making is carried out at the stage of pre-project preparation, which includes the modeling of basic operations using finite element or analytical models according to the developed algorithm. The article assesses the power parameters of reverse extrusion using two well-known methods, taking into account the difference in thickness of the forgings obtained. An attempt was made to stamping casting tin bronzes, a microstructural analysis was carried out, which showed the need to use homogenizing annealing of billets or the use of deformable grades of tin bronzes.
Keywords: reverse extrusion; decision making; algorithm; power parameters; cast bronze; microstructure.

Yu. N. Loginov (The Ural Federal University named after the first President of Russia B. N. Yeltsin, Institute of Physics of Metals named after M. N. Mikheev Ural Branch of the Russian Academy of Sciences, Ekateriburg), Yu. V. Zamaraeva (The Ural Federal University named after the first President of Russia B. N. Yeltsin, Ekateriburg), B. I. Kamenetsky (Institute of Physics of Metals named after M.N. Mikheev Ural Branch of the Russian Academy of Sciences, Ekateriburg)

Angular strips extrusion modeling in 3D setting

The results of modeling of angular extrusion by the finite element method are presented in the DEFORM software module. The difference of the solution is the three-dimensional formulation of the problem for the case of pressing magnesium. This made it possible to reveal heterogeneities in the distribution of strains and stresses. It was concluded that the strains at the upper edge of the pressed strip increased to 40% relative to strains at the lower edge. An increase in the level of hardening on the edges of the strip was also revealed, which will have to be taken into account during the subsequent sheet rolling.
Keywords: angle extrusion; deformation; stress; magnesium; finite element method; software module DEFORM.

A. E. Tsibulko, E. A. Romanenko (PJSC «NKZM», Kramatorsk, Ukraine)

About unified strength theories

An overview of the history of the development of unified theories of strength is shown. The main achievements of outstanding scientists in this field are considered. An analysis of the advantages and disadvantages of the existing unified theories of strength, based on energy and other concepts is presented. Examples are given concerning the choice of the theory in question.
Keywords: theory of strength; destruction; mechanical properties; fatigue strength; normal stress; tangential stress; deformation; potential energy; separation; shear.