Strength of Materials

, Volume 25, Issue 5, pp 355–362 | Cite as

Evaluation of the fracture toughness of structural steels under high-speed deformation

  • V. I. Kir'yan
  • A. P. Vashchenko
  • L. A. Volgin
  • S. V. Shamanovskii
Scientific-Technical Section
  • 23 Downloads

Abstract

We investigated the dynamic crack resistance (fracture toughness) of low-alloy structural steels within a broad range of change of temperature (173–323°K) and loading rate (10−5−120 m/sec) on standard specimens tested under conditions of three-point bending by a drop weight. As velocity parameters determining the conditions of high-speed deformation of metal in the zone of prefailure we considered the speed of opening of the crack tip δ and the rate of local plastic deformation έ on the contour of its blunted tip. To calculate έ in dependence on the loading conditions, the corresponding expression is presented. We evaluated experimentally the mechanical properties of the investigated steels at different temperatures T and strain rates, and we also considered the possibility of determining theoretically the dynamic yield strength\(\sigma _{0.2} ^d \) that is used in establishing the value of\(\dot \varepsilon \). We present the correlation between the transition temperature of the metal to ductile failure Tv and the velocity parameters\(\dot \delta , \dot \varepsilon \).

Keywords

Plastic Deformation Transition Temperature Yield Strength Fracture Toughness Loading Condition 

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Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • V. I. Kir'yan
    • 1
    • 2
  • A. P. Vashchenko
    • 1
    • 2
  • L. A. Volgin
    • 1
    • 2
  • S. V. Shamanovskii
    • 1
    • 2
  1. 1.E. O. Paton Institute of Electric WeldingAcademy of Sciences of the UkraineUSSR
  2. 2.Institute of the Strength of MaterialsAcademy of Sciences of the UkraineKiev

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