The effect of discontinuous crack in creep crack growth tests

Nak Hyun Kim, Yun Jae Kim, Catrin M. Davies, Ali Mehmanparast, Kamran M. Nikbin

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Discontinuous cracks ahead of the leading crack tip may be present in observedcertain creep crack growth tests as well as in components. In this work, a single crack of different dimensions and distance from the leading crack has been numerically modeled in a compact tension specimen using elastic, elastic-plastic and elastic-plastic-creep loading. In order to examine their effects on fracture mechanics parameters a sensitivity analysis was performed to determine the effects of size and distance of the secondary crack with respect to the main crack. t The elastic analysis shows that the compliance is insensitive small cracks ahead of the main crack. Limit load analyses, assuming an elastic-perfectly plastic material, show that the limit load decreases due to the presence of discontinuous cracks ahead of the main crack. Theload versus plastic load-line displacement response of the specimen was significantly influenced by discontinuous cracking. The J contour parameter and C *-integral have been evaluated at the three crack tips and the average of all of them derived for the appropriate contours were compared with the valuesobtained from on ASTM E1820(1) and E1457(2). Whilst the average values of the contour integral are similar to the ASTM J and C* values there is significant differences in J and C * for the individual crack tip values. This need to be further evaluated in future work.

Original languageEnglish
Title of host publicationASME 2013 Pressure Vessels and Piping Conference, PVP 2013
DOIs
Publication statusPublished - 2013 Dec 1
Externally publishedYes
EventASME 2013 Pressure Vessels and Piping Conference, PVP 2013 - Paris, France
Duration: 2013 Jul 142013 Jul 18

Publication series

NameAmerican Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP
Volume6 A
ISSN (Print)0277-027X

Conference

ConferenceASME 2013 Pressure Vessels and Piping Conference, PVP 2013
CountryFrance
CityParis
Period13/7/1413/7/18

Fingerprint

Crack propagation
Creep
Cracks
Crack tips
Plastics
Load limits
Fracture mechanics
Sensitivity analysis

ASJC Scopus subject areas

  • Mechanical Engineering

Cite this

Kim, N. H., Kim, Y. J., Davies, C. M., Mehmanparast, A., & Nikbin, K. M. (2013). The effect of discontinuous crack in creep crack growth tests. In ASME 2013 Pressure Vessels and Piping Conference, PVP 2013 (American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP; Vol. 6 A). https://doi.org/10.1115/PVP2013-98142

The effect of discontinuous crack in creep crack growth tests. / Kim, Nak Hyun; Kim, Yun Jae; Davies, Catrin M.; Mehmanparast, Ali; Nikbin, Kamran M.

ASME 2013 Pressure Vessels and Piping Conference, PVP 2013. 2013. (American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP; Vol. 6 A).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Kim, NH, Kim, YJ, Davies, CM, Mehmanparast, A & Nikbin, KM 2013, The effect of discontinuous crack in creep crack growth tests. in ASME 2013 Pressure Vessels and Piping Conference, PVP 2013. American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP, vol. 6 A, ASME 2013 Pressure Vessels and Piping Conference, PVP 2013, Paris, France, 13/7/14. https://doi.org/10.1115/PVP2013-98142
Kim NH, Kim YJ, Davies CM, Mehmanparast A, Nikbin KM. The effect of discontinuous crack in creep crack growth tests. In ASME 2013 Pressure Vessels and Piping Conference, PVP 2013. 2013. (American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP). https://doi.org/10.1115/PVP2013-98142
Kim, Nak Hyun ; Kim, Yun Jae ; Davies, Catrin M. ; Mehmanparast, Ali ; Nikbin, Kamran M. / The effect of discontinuous crack in creep crack growth tests. ASME 2013 Pressure Vessels and Piping Conference, PVP 2013. 2013. (American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP).
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