Study of the residual stress state during plastic deformation under uniaxial tension in a 5.0Cr and 0.5Mo steel

Journal Article · Thu May 01 04:00:00 EDT 1997 · Scripta Materialia

DOI:https://doi.org/10.1016/S1359-6462(96)00475-7· OSTI ID:474219

Gurova, T; Teodosio, J R; Rebello, J M.A. ^[1]; Monin, V ^[2]

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1. Univ. Federal do Rio de Janeiro (Brazil). Dept. of Metallurgical and Materials Engineering
2. Saint Petersburg Technical Univ. (Russian Federation)

Shot-peening is a surface treatment for metals largely used to increase their fatigue resistance. According to some authors, shot-peening gives rise to residual compressive stress in the surface layers of the metals, which could explain the fatigue resistance improvement. This is quite reasonable as this compressive stress reduces the net effect of the tensile component of the applied cyclic loading. This effect increases the fatigue resistance. There is however another point of view on this subject that ascribes less importance to the residual compressive stress influence. It is based upon work which shows that cyclic loading promotes residual surface stress modification by a mechanism of local plastic microdeformation. Since in this case a surface stress decrease would occur, these papers report that in the early applied cycles, residual stress could not have any influence on the ultimate fatigue behavior of the metal. This point of view highlights the need for a study to clarify the influence of plastic deformation upon relaxation as a function of variation of the initial surface residual stress. The aim of the present work is to provide a better understanding of these questions. Steel samples of 5Cr-0.5Mo (weight percent) were submitted to shot-penning in order to build up compressive surface residual stress. The samples were plastically deformed by uniaxial tensile test until complete fracture. Longitudinal and transverse residual stresses were measured before and during the test.

• OSTI ID: 474219
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 9 Vol. 36; ISSN 1359-6462; ISSN SCMAF7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMIUM STEELS
DEFORMATION
FRACTURES
LOW ALLOY STEELS
MOLYBDENUM ADDITIONS
RESIDUAL STRESSES
SHOT PEENING
SURFACE PROPERTIES
TENSILE PROPERTIES