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Strength of Materials

, Volume 23, Issue 11, pp 1169–1176 | Cite as

X-ray method of evaluating local state of stress of material at crack tip in one-time loading

  • G. V. Klevtsov
  • L. R. Botvina
  • N. A. Gorbatenko
  • V. G. Kudryashov
  • R. G. Klevtsov
Scientific-Technical Section

Abstract

The article deals with the fractographic traits of failure and the regularities of the formation of zones of plastic deformaton in materials with bcc lattice (steels 20, 40, 45, St. 3, 15Kh2MFA) and with fee lattice (alloy D16 and the austenitic steels 40G18F, 40Kh4G18F, 03Khl3AG19) under different kinds of one-time loading: static, impact, high-speed impulsive. It is shown that the local state of stress of the material at the crack tip with all the mentioned kinds of loading can be evaluated by the single criterion hmax/t (the ratio of the maximal depth of the zone of plastic deformation under the fracture surface to the thickness of the specimen). Three regions of local state of stress are identified: hmax/t < 10−2 close to plane strain (PD), hmax/t > 10−1 close to plane stress (PD), and 10−2 < hmax/t < 10−1 the transient region from PD to PS. In static crack resistance tests of materials the known criterion t(k/σ0.2)2 ≥ 2.5 separates PS from the transient region in materials with fee lattice, and in materials with bcc the transient region from PD. In materials not undergoing phase transformations at failure, the correlation of the criterion hmax/t and the ratio β/β0 is described by a single curve, independently of the form of loading. In regions close to PD and PS the ratio β/β0 can be used for evaluating the local state of stress of the material at the crack tip.

Keywords

Local State Plane Strain Plane Stress Austenitic Steel Resistance Test 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Publishing Corporation 1992

Authors and Affiliations

  • G. V. Klevtsov
    • 1
    • 2
    • 3
  • L. R. Botvina
    • 1
    • 2
    • 3
  • N. A. Gorbatenko
    • 1
    • 2
    • 3
  • V. G. Kudryashov
    • 1
    • 2
    • 3
  • R. G. Klevtsov
    • 1
    • 2
    • 3
  1. 1.Polytechnic InstituteBishkek
  2. 2.Institute of MetallurgyAcademy of Sciences of theUSSRUSSR
  3. 3.All-Union Institute of Light AlloysMoscow

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