Evaluation of the influence of residual stresses on ductile fracture
2011 (English)Conference paper (Refereed)
In this work the significance of residual stresses for ductile fracture was investigated. The treatment of residual stresses as expressed in fracture assessment procedures such as the R6 method is believed to be very conservative for ductile materials, when fracture occurs at high primary loads. Earlier numerical studies have reinforced this belief. Tests on notched 3PB specimens with and without residual stresses were conducted on two ferritic steels. The residual stresses were introduced by applying a compressive pre-load on notched specimens. The tests were designed to achieve crack initiation at load levels around the limit load. The crack growth in the tests was measured by a compliance method and by colour marking of the crack surface. The crack-tip driving force J was evaluated numerically for specimens with and without residual stresses. The experimental results show that the residual stresses clearly contribute to J at low primary loads. However, this contribution diminishes as the primary loads increase. The experimental results were also compared with results evaluated using the R6 procedure. These comparisons revealed an overly high conservativeness in R6 for cases with residual stresses compared to the conservativeness for cases without residual stresses.
Place, publisher, year, edition, pages
2011. no PARTS A AND B, 347-356 p.
, American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP, ISSN 0277-027X ; 6
Compliance method, Crack surfaces, Driving forces, Ductile materials, Fracture assessment, Notched specimens, Primary loads, R6 procedure, Cracks, Ductile fracture, Loads (forces), Pressure vessels, Residual stresses
IdentifiersURN: urn:nbn:se:kth:diva-148715DOI: 10.1115/PVP2011-58080ISI: 000320566000045ScopusID: 2-s2.0-84881411864OAI: oai:DiVA.org:kth-148715DiVA: diva2:746016
ASME 2011 Pressure Vessels and Piping Conference, PVP 2011, 17 July 2011 through 21 July 2011, Baltimore, MD, United States
QC 201409112014-09-112014-08-112014-09-11Bibliographically approved