High Cycle Fatigue Performance in Laser Shock Peened TC4 Titanium Alloys Subjected to Foreign Object Damage

Journal Article · Thu Mar 15 04:00:00 EDT 2018 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1007/S11665-018-3172-6· OSTI ID:22858052

Luo, Sihai; Nie, Xiangfan; Zhou, Liucheng; Li, Yiming; He, Weifeng ^[1]

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1. Air Force Engineering University, Science and Technology on Plasma Dynamics Laboratory (China)

During their service, titanium alloys are likely to suffer from the foreign object damage (FOD), resulting in a decrease in their fatigue strength. Laser shock peening (LSP) has been proved to effectively increase the damage tolerance of military engine components by introducing a magnitude compressive residual stress in the near-surface layer of alloys. In this paper, smooth specimens of a TC4 titanium alloy were used and treated by LSP and subsequently exposed to FOD, which was simulated by firing a steel sphere with a nominal velocity of 300 m/s, at 90° with the leading edge of the LSP-treated region using a light gas gun. All impacted specimens were then subjected to fatigue loading. The results showed that LSP could effectively improve the fatigue strength of the damaged specimens. The effect of LSP on the fatigue strength was assessed through fracture observations, microhardness tests and residual stress analyses. The residual stresses due to the plastic deformation caused by LSP and the FOD impact, which were found to play a crucial role on the fatigue strength, were determined using the commercial software ABAQUS.

• OSTI ID: 22858052
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 3 Vol. 27; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPUTERIZED SIMULATION
FATIGUE
FRACTURES
LASER RADIATION
LAYERS
MICROHARDNESS
PLASTICITY
RESIDUAL STRESSES
STEELS
STRESS ANALYSIS
SURFACES
TITANIUM ALLOYS