THE INFLUENCE OF STRAIN RATE ON THE STRENGTH THE CONSTRUCTIONAL LOW-ALLOY STEEL

KYZIOŁ Lesław, Faculty of Marine Engineering, Gdynia Maritime University, Gdynia, Poland,This email address is being protected from spambots. You need JavaScript enabled to view it."> This email address is being protected from spambots. You need JavaScript enabled to view it., This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.

The article presents the results of the influence strain rates on the increase in strength of tested constructional steel. Elastic deformation simply involves stretching of atoms away from their equilibrium separation. Plastic deformation occurs through collective movement of atom planes. Therefore, you should first estimate the stress required to move one plane across another. The dislocations are the basis for plastic deformation. The formation and interaction of dislocations require an analysis of the issues of plastic deformation, the effect of temperature, strain rate and the stress-strain. Johnson and Cook proposed the unified constitutive laws. The Equation Johnson and Cook includes a strain hardening term, a strain-rate term, and a temperature-dependence term. This equation describes well the results of research. Studies have shown that the growth strain rate very substantially affect the increase in strength properties of the constructional steel 15G2ANb.

steel, dynamic properties of steel, strain rate, dislocations

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