Effects of surface curvature on residual stress field of 316L stainless steel subjected to laser shock peening

Laser shock peening (LSP) is an innovative surface treatment technique similar to shot peening. An analytical model to predict the residual stress field can obtain the impact effect much quickly, and will be invaluable in enabling a close-loop process control in production, saving time and cost of processing. A complete analytical model of LSP with some reasonable simplification is proposed to predict residual stresses in depth by a sequential application of a confined plasma development model and a residual stress model. The spatial distribution of the shock pressure and the high strain rate effect are considered in the model. Good agreements have been shown with several experimental measured results for various laser conditions and target materials, thus proving the validity of the proposed model.

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INVESTIGATION OF RESIDUAL STRESS FIELD IN THE CURVED SURFACE OF ROUND ROD SUBJECTED TO MULTIPLE LASER SHOCK PEENING

Surface Review and Letters ◽

10.1142/s0218625x21500293 ◽

2021 ◽

pp. 2150029

Author(s):

XINGQUAN ZHANG ◽

WENWU NIU ◽

YUANDE YIN ◽

JINXIU FANG ◽

SYED SOHAIL AHMAD SHAH ◽

...

Keyword(s):

Residual Stress ◽

Finite Element Analysis ◽

Stress Field ◽

Compressive Residual Stress ◽

Laser Shock Peening ◽

Curved Surface ◽

Laser Shock ◽

Residual Stress Field ◽

Element Analysis ◽

Shock Peening

Laser shock peening (LSP) was employed to squeeze compressive residual stress (CRS) into the curved surface of the round rod with diameter of 16[Formula: see text]mm. The residual stress field was induced by nine laser shots irradiating at different locations along the specified path. The developing process of the residual stress field was investigated with finite element analysis, and the corresponding experiments were also carried out to validate the calculated results. Results demonstrate that multiple LSP with 50% overlapping rate can result in residual stress field with the maximum CRS varying from 155.2[Formula: see text]MPa to 198.8[Formula: see text]MPa along the direction of the rod axis. The peened surface appears wavy in shape and the maximum depth of plastic deformation in the curved surface is 13.41[Formula: see text][Formula: see text]m. The value of surface roughness increases from 3.87[Formula: see text][Formula: see text]m to 4.65[Formula: see text][Formula: see text]m.

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Residual stress in geometric features subjected to laser shock peening

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406214550511 ◽

2014 ◽

Vol 229 (11) ◽

pp. 1923-1938 ◽

Cited By ~ 1

Author(s):

M Achintha ◽

D Nowell

Keyword(s):

Residual Stress ◽

Stress Field ◽

Structural Integrity ◽

Laser Shock Peening ◽

Geometric Features ◽

Laser Shock ◽

Computationally Efficient ◽

Residual Stress Field ◽

Subsequent Performance ◽

Shock Peening

This article reports selected findings from a collaborative research study into the fundamental understanding of laser shock peening (LSP), when applied to key airframe and aero-engine alloys. The analyses developed include explicit simulations of the peening process together with a simpler eigenstrain approach, which may be used to provide an approximation to the residual stress field in a number of geometries. These are chosen to represent parts of structural components under conditions relevant to service applications. The article shows that the eigenstrain approach can provide good approximations to the stress field in most circumstances and may provide a computationally efficient tool for exploring different peening strategies. Both explicit and eigenstrain results demonstrate that the interaction between the LSP process and geometric features is important for understanding the subsequent performance of components. Particularly relevant for engineering applications is that not all instances of LSP application may provide an improvement in structural integrity.

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