Moscow Polytechnic University, Moscow, Russia

N. F. Shpunkin, Cand. Eng., Prof., Dept. of Materials Forming and Additive Technologies, e-mail: snf48@yandex.ru

The application region of the testing machine MTL-10G-1 is considered, provided in accordance with the technical documentation of the manufacturer and consisting in conducting a standard test of thin-sheet metals by the Eriksen method. It is noted that the technological capabilities of the machine are not limited to this type of testing, but can be used to perform various types of investigation of the sheet materials’ properties. Such possibilities are due to the fact that, according to the principle of operation, the machine is a double-acting press, and the experimental equipment installed on the machine can perform clamping and plastic deformation of sheet metal. This paper considers the possibilities of using the machine to conduct various types of tests that differ from the Eriksen method (a test for biaxial tension with preservation of flatness in the test area, a test for torsion of a sheet specimen in its plane, etc.). The experience of using the machine for experimental investigations of the behavior of sheet materials in various sheet stamping operations, such as forming, drawing and stretching, is presented. The possible region of application of the machine for testing and debugging the production technologies for stamping, the basis of which is the operation of extraction, is indicated. The machine’s capabilities provide testing to evaluate and refine the plastic properties of sheet metals. With the use of special test equipment, experimental data can be obtained to construct a diagram of extreme deformations, which is the most important characteristic used to predict the destruction of a stamped sheet blank. This characteristic determines the ratio of deformations occurring in the sheet, at which destruction occurs. This knowledge is especially important for new types of deformable sheet steels of increased strength, mastered by the metallurgical industry.

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