Effects of laser peening on the fatigue strength and defect tolerance of aluminum alloy

• Takahashi, Koji

• Kogishi, Yuta

• Shibuya, Norihito

• Kumeno, Fumiaki

Abstract

The effects of laser peening (LP) on the bending fatigue strength of the 7075‐T651 aluminum alloy were investigated. Accordingly, the defect tolerance of the aluminum alloy subjected to LP is discussed on the basis of fracture mechanics. The results indicate that a deeper compressive residual stress was induced by LP compared with the case of shot peening (SP). The fatigue strengths increased when both peening types were used. Semicircular slits with depths less than 0.4 and 0.1 mm were rendered harmless on the basis of the applications of LP and SP, respectively. The apparent threshold stress intensity factor range ΔK_(th,ap) increased by approximately five and two times owing to LP and SP, respectively. The increase of the ΔK_(th,ap) was caused by the compressive residual stress induced by the peening. The Kitagawa‐Takahashi diagram of the laser‐peened specimens shows that the defect tolerance of the aluminum alloy was improved by LP.

This is the peer reviewed version of the following article: Takahashi et al, FFEMS, 2020, which has been published in final form at https://doi.org/10.1111/ffe.13201. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.

Journal

• Fatigue & Fracture of Engineering Materials & Structures

  Fatigue & Fracture of Engineering Materials & Structures 2020-01-24

  Wiley

Keywords

• aluminum alloy
• defect tolerance
• fatigue strength
• laser peening
• residual stress
• shot peening

Details

• CRID: 1050565163714520832
• NII Article ID: 120006796067
• ISSN: 14602695
• Web Site: http://hdl.handle.net/10131/00012915
• Text Lang: en
• Article Type: journal article
• Data Source:
  • IRDB
  • CiNii Articles