Effect study and application to improve high cycle fatigue resistance of TC11 titanium alloy by laser shock peening with multiple impacts

Laser shock peening (LSP) is an effective surface treatment for improving fatigue resistance of metallic materials, in which high-amplitude beneficial residual stresses and structure changes can be produced. In aero-engines, the compressor blade made of TC11 titanium alloy was prone to result in hig...

Full description

Saved in:
Bibliographic Details
Published in:Surface & coatings technology 2014-08, Vol.253, p.68-75
Main Authors: Nie, Xiangfan, He, Weifeng, Zang, Shunlai, Wang, Xuede, Zhao, Jie
Format: Article
Language:English
Subjects:
Applied sciences
Cross-disciplinary physics: materials science
rheology
Exact sciences and technology
Fatigue
High cycle fatigue
Laser shock peening
Laser shock processing
Materials science
Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology
Metals. Metallurgy
Microhardness
Microstructure
Nanostructure
Physics
Residual stress
Strengthening
Strengthening mechanism
Surface treatments
TC11 titanium alloy
Titanium base alloys
Vibration
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Laser shock peening (LSP) is an effective surface treatment for improving fatigue resistance of metallic materials, in which high-amplitude beneficial residual stresses and structure changes can be produced. In aero-engines, the compressor blade made of TC11 titanium alloy was prone to result in high cycle fatigue (HCF) failure. The aim of this paper was to utilize LSP with befitting parameters to improve the HCF performance of TC11 titanium alloy. Firstly, the microstructure and mechanical properties of TC11 titanium alloy with different LSP impacts were observed and measured via transmission electron microscope (TEM), residual stress tester and microhardness tester. High-density dislocations and nanostructure were observed in the surface layer. High-amplitude compressive residual stresses were induced and microhardness was remarkably improved. According to the effects, a set of LSP parameters with three LSP impacts was confirmed and applied on standard vibration specimens. Vibration fatigue tests were conducted to validate the strengthening effect on HCF strength. The fracture mechanism was analyzed by fracture analysis. The strengthening mechanism of LSP was indicated by establishing the relationship between fatigue characteristics and effects on residual stress and microstructural changes. •High-density dislocations and nanostructure are generated after LSP processing.•With LSP impacts increased, nano-grains get smaller and more uniform.•The fatigue strength of TC11 titanium alloy is improved from 483.2MPa to 593.6MPa.•The strengthening mechanism was indicated by LSP effects for fatigue behavior.
ISSN:0257-8972
1879-3347
DOI:10.1016/j.surfcoat.2014.05.015