Effect of grain boundary character on nucleation of intergranular fatigue cracks in SUS430 ferritic stainless steel

• YANG Weitao

  Department of Information Science and Manufacturing Engineering, Graduate School of Engineering, Ashikaga Institute of Technology

• KOBAYASHI Shigeaki

  Division of Mechanical Engineering, Department of Innovative Engineering, Ashikaga Institute of Technology

• SAITO Sakae

  Division of Mechanical Engineering, Department of Innovative Engineering, Ashikaga Institute of Technology

Bibliographic Information

Other Title

• SUS430フェライト系ステンレス鋼の粒界疲労き裂形成に及ぼす粒界性格の影響

Abstract

The effect of grain boundary character and grain boundary geometrical configuration on nucleation of intergranular fatigue crack in SUS430 ferritic stainless steel was quantitatively investigated to reveal the elementary process of high cycle fatigue fracture. The grain boundary microstructure in the pre- and post-fatigued specimen was evaluated by scanning electron microscopy/ electron backscatter diffraction (SEM/EBSD) technique. Fatigue crack nucleation occurred mainly at grain boundaries at the low stress amplitude level. On the other hand, nucleated fatigue cracks were propagated immediately to perpendicular to the stress direction at the high stress amplitude level, regardless of the grain interior or grain boundaries. In the case of low stress amplitude level, intergranular fatigue cracks preferentially nucleated at high-angle random boundaries, although the fatigue cracks never nucleated at low-angle boundaries. Fatigue cracks nucleated at low-∑ coincidence site lattice (CSL) boundaries only when the trace of grain boundaries on the specimen surface was parallel to persistent slip bands (PSBs), although the fatigue cracking at random boundaries was accelerated even when the trace of grain boundary on the specimen surface was not parallel to PSBs in neighbouring grains. Fatigue crack nucleation was hardly affected by the geometrical arrangements between the trace of grain boundary on the specimen surface and the stress axis. The grain boundary engineering for control of intergranular fatigue cracking was discussed on the basis of the results of the grain boundary character-dependent intergranular fatigue crack nucleation.

Journal

• Transactions of the JSME (in Japanese)

  Transactions of the JSME (in Japanese) 83 (847), 16-00460-16-00460, 2017

  The Japan Society of Mechanical Engineers

Keywords

• High-cycle fatigue
• Fatigue crack nucleation
• Grain boundary character
• Grain boundary geometrical configration
• Ferritic stainless steel

Details

• CRID: 1390001205516828672
• NII Article ID: 130006320999
• DOI: 10.1299/transjsme.16-00460
• ISSN: 21879761
• Web Site: https://www.jstage.jst.go.jp/article/transjsme/83/847/83_16-00460/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed