Effect of Laser Shock Peening on Fatigue Life of Full Scale Turbine Blades

Laser shock peening (LSP) is a promising surface treatment method for improving fatigue properties of turbine blades. The effect of LSP on combined low and high cycle fatigue (CCF) life of full scale turbine blade was investigated. The LSP is performed by YLSS-40 LSP equipment and the laser power density is 5.8 GW/cm2. Thirteen LSP treated turbine blades and thirteen untreated turbine blades were selected to carry out the contrast test at high temperature in a bench environment. Experimental results show that there exists a critical vibration stress of blades, below which the CCF life was significantly prolonged by LSP, and above which the LSP has no effect or an adverse effect on the CCF life. The safe life of blades can be significantly increased after treated by LSP when the total stress is below the yield stress. However, the situation is a bit different when the total stress is above the yield stress. Although the safe life of LSP blades is longer than that of untreated blades in this situation, but the median life of blades is decreased after treated by LSP. The effect of LSP on the scatter in life plays a greater role in improving the safe life that directly leads to the safe life of LSP blades longer than the safe life of untreated blades when the total stress is above the yield stress.

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The effect of rolling contact fatigue properties on 316 stainless steel under laser shock peening

Optics & Laser Technology ◽

10.1016/j.optlastec.2021.107159 ◽

2021 ◽

Vol 141 ◽

pp. 107159

Author(s):

Fengze Dai ◽

Wei Cheng ◽

Yueyang Zheng ◽

Xizhang Chen

Keyword(s):

Stainless Steel ◽

Rolling Contact Fatigue ◽

Contact Fatigue ◽

Rolling Contact ◽

Laser Shock Peening ◽

Fatigue Properties ◽

Laser Shock ◽

316 Stainless Steel ◽

Shock Peening

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The Influence of Laser Shock Peening on Fatigue Properties of AA2024-T3 Alloy with a Fastener Hole

Metals ◽

10.3390/met10040495 ◽

2020 ◽

Vol 10 (4) ◽

pp. 495

Author(s):

Ruslan Sikhamov ◽

Fedor Fomin ◽

Benjamin Klusemann ◽

Nikolai Kashaev

Keyword(s):

Fatigue Life ◽

Fatigue Cracks ◽

Initial Crack ◽

Fatigue Tests ◽

Laser Shock Peening ◽

Fatigue Properties ◽

Hole Drilling ◽

Laser Shock ◽

Fastener Hole ◽

Shock Peening

The objective of the present study was to estimate the influence of laser shock peening on the fatigue properties of AA2024-T3 specimens with a fastener hole and to investigate the possibility to heal the initial cracks in such specimens. Fatigue cracks of different lengths were introduced in the specimens with a fastener hole before applying laser shock peening. Deep compressive residual stresses, characterized by the hole drilling method, were generated into the specimens by applying laser shock peening on both sides. Subsequently, the specimens were subjected to fatigue tests. The results show that laser shock peening has a positive effect regarding the fatigue life improvement in the specimens with a fastener hole. In addition, laser shock peening leads to a healing effect on fatigue cracks. The efficiency of this effect depends on the initial crack length. The effect of laser shock peening on the fatigue life periods was determined by using resonant frequency graphs.

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3D laser shock peening – A new method for improving fatigue properties of selective laser melted parts

Additive Manufacturing ◽

10.1016/j.addma.2020.101112 ◽

2020 ◽

Vol 33 ◽

pp. 101112 ◽

Cited By ~ 3

Author(s):

Nikola Kalentics ◽

Manuel Ortega Varela de Seijas ◽

Seth Griffiths ◽

Christian Leinenbach ◽

Roland E. Logé

Keyword(s):

Laser Shock Peening ◽

New Method ◽

Fatigue Properties ◽

Laser Shock ◽

Shock Peening

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Influence of multiple laser impacts on thin leading edges of turbine blade

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420719873936 ◽

2019 ◽

Vol 234 (1) ◽

pp. 130-143

Author(s):

M Ayeb ◽

M Frija ◽

R Fathallah

Keyword(s):

Turbine Blade ◽

Turbine Blades ◽

Leading Edge ◽

Laser Shock Peening ◽

Experimental Investigations ◽

Laser Shock ◽

Special Effect ◽

Shock Peening ◽

Critical Components ◽

Mechanical Surface

Laser shock peening is a mechanical surface improvement treatment used to enhance the fatigue life of critical components. This paper investigates the influence of multiple square laser impacts to study their special effect on the diverse mechanical behaviours of the thin leading edge surface of turbine blades. Most works existing in the literature have presented experimental investigations. The originality of our paper is to validate and numerically simulate the proposed model. Indeed, a 3D finite element method of a thin leading edge specimen, Ti–6Al–4V, of a turbine blade is numerically simulated using the ABAQUS software. The mechanical surface modifications (residual stresses, equivalent plastic strains and Johnson–Cook superficial damage) induced by the multiple square laser impact are examined in detail. The main purpose of this investigation is to determine the effects of single-sided and double-sided laser shock peening.

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Residual Stress State and Fatigue Behaviour of Laser Shock Peened Titanium Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.129 ◽

2006 ◽

Vol 524-525 ◽

pp. 129-134 ◽

Cited By ~ 3

Author(s):

I. Altenberger ◽

Yuji Sano ◽

M.A. Cherif ◽

Ivan Nikitin ◽

Berthold Scholtes

Keyword(s):

Residual Stress ◽

Titanium Alloys ◽

Cold Work ◽

Fatigue Behaviour ◽

Laser Shock Peening ◽

Fatigue Properties ◽

Stress Profile ◽

Laser Shock ◽

Near Surface ◽

Shock Peening

Laser shock peening is a very effective mechanical surface treatment to enhance the fatigue behaviour of highly stressed components. In this work the effect of different laser shock peening conditions on the residual stress depth profile and fatigue behaviour without any sacrificial coating layer is investigated for two high strength titanium alloys, Ti-6Al-4V and Timetal LCB. The results show that the optimization of peening conditions is crucial to obtain excellent fatigue properties. Especially, power density, spot size and coverage severely influence the residual stress profile of laser shock peened Ti-6Al-4V and Timetal LCB specimens. For both alloys, subsurface as well as surface compressive residual stress peaks can be obtained by varying the peening conditions. In general, Timetal LCB exhibits steeper stress gradients than Ti-6Al-4V for identical peening conditions. The main parameters affecting the fatigue life are near-surface cold work and compressive residual stresses.

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