Fatigue strength of high-strength steel after shipyard production process of plasma cutting, grinding, and sandblasting

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • Technische Universität Hamburg
  • Meyer Turku Oy

Abstract

This paper investigates experimentally the fatigue strength of high-strength steel, which has undergone the normal shipyard production process of plasma cutting, grinding, and sandblasting. The study includes steels with the yield strength of 355 and 690 MPa. The tested specimens are of dog-bone shape and represent the large-scale situation of a cruise ship balcony opening corner, loaded in shear or tension. The influence of surface roughness, internal inclusions, hardness, and residual stress on the fatigue strength are studied and discussed. Compared to the design curve as well as to the untreated surfaces, the results show significantly improved fatigue strength under constant amplitude loading at a load ratio of R = 0.1. However, very flat or even rising slope of the S-N curve indicates variations in the material and surface quality as well as in the residual stress. Surprisingly, internal defects even up to 100 μm in size did not decrease the fatigue strength.

Details

Original languageEnglish
Pages (from-to)1273-1284
Number of pages12
JournalWelding in the World
Volume62
Issue number6
Publication statusPublished - Nov 2018
MoE publication typeA1 Journal article-refereed

ID: 31331879