BUILDING OF A REAL DIAGRAM OF DEFORMATION THROUGH THE EXAMPLE OF THIN-WALLED CYLINDRICAL SLEEVE WITH THICKNESS DEVIATION WITH BOTTOMS, MADE OF STEEL 20
Dmytriienko Roman, Paton Electric Welding Institute of NAS of Ukraine (11 Bozhenka Str., 03680 Kyiv, Ukraine).
Paliienko Oleksandr, Paton Electric Welding Institute of NAS of Ukraine (11 Bozhenka Str., 03680 Kyiv, Ukraine).
Urgency of the research. After the qualification tests for steel cylinders static pressure to failure due to plastic deformation, it is not possible to reliably determine the mechanical properties of steel on standard flat samples cut in the aftermath of the housing. And this is true in cases where the tank is presented in a single copy and collapsed at pressures lower than required. And that was the reason for this, no defect detected, or too low mechanical properties sometimes have to guess only.
Target setting. To analyze the mechanical properties of steel, obtained on standard flat samples after preliminary plastic deformation as part of its thin-walled cylindrical shell with end plates.
Actual scientific researches and issues analysis. Most of the publications of the unity of the deformation curve is based mainly on tests of torsion and tension.
Uninvestigatigated parts of general matters defining. The principle of recovery of deformation curve after single test cylinder internal pressure is lit very weakly.
The research objective. Tracing the relationship of mechanical properties of steel, a standard method for a preliminary plastic deformation of a part of the thin-walled cylindrical vessel with bottoms.
The statement of basic materials. Handpainted plastic deformation process first began in a biaxial stress state realized in a thin-walled shell bottoms with a loaded under internal pressure, and then a uniaxial - with standard flat samples tests. In both cases, the loading was simple - a voltage proportional to the load.
Conclusions. The studies confirm the existence of a single strain curve, regardless of the loading sequence. Fixing the residual deformation of thin-walled circular cylindrical steel container allows you to restore the true strain diagram.
deformation, the internal pressure test, tensile strength, tensile specimens stress intensity, approximation
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