0

Full Content is available to subscribers

Subscribe/Learn More  >

Effect of Non-Proportional Loading on Fatigue Crack Initiation and Growth Behavior of Maraging Steel

[+] Author Affiliations
Hiroshi Nakamura

IHI Corporation, Tokyo, Japan

Masahiro Takanashi

IHI Corporation, Yokohama, Japan

Tatsuya Masaki, Shengde Zhang, Masao Sakane

Ritsumeikan University, Shiga, Japan

Paper No. GT2012-68931, pp. 241-248; 8 pages
doi:10.1115/GT2012-68931
From:
  • ASME Turbo Expo 2012: Turbine Technical Conference and Exposition
  • Volume 7: Structures and Dynamics, Parts A and B
  • Copenhagen, Denmark, June 11–15, 2012
  • Conference Sponsors: International Gas Turbine Institute
  • ISBN: 978-0-7918-4473-1
  • Copyright © 2012 by ASME

abstract

This paper deals with multiaxial low cycle fatigue (LCF) crack behavior of maraging steel under non-proportional loading. Strain controlled LCF tests under proportional and non-proportional loading with 90° out-of-phase shift between the axial and shear strains were carried out on tube specimens at room temperature. In the correlation with Mises strain, LCF lives under non-proportional loading were underestimated by a factor of 10 from those under proportional loading. Observation of the specimen surface during fatigue tests showed that a large number of cracks were initiated in shear loading and non-proportional loading compared with uniaxial loading. Finite element analyses for estimating the stress concentration around inclusions revealed that the inclusion under shear loading and non-proportional loading had more locations to initiate cracks than the inclusion under uniaxial loading. The crack initiation life under proportional loading did not significantly differ from that under non-proportional loading. Fatigue cracks under non-proportional loading, however, propagated faster than those under proportional loading. The faster fatigue crack propagation under nonproportional loading presumably results from higher strain intensity at crack tips than that under proportional loading. The fatigue lives were predicted from the crack propagation analysis. Most calculated lives were within a factor of 2 scatter band so that the correlation of the test results appears satisfactory. Therefore, the main cause of shorter fatigue life under non-proportional loading resulted from the faster crack growth due to the higher strain intensity.

Copyright © 2012 by ASME
Topics: Steel , Fatigue cracks

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In