Investigation on impact pressure and residual stress of water jet peening on AL6061-T6 with an inclined surface

Stainless steel clad plate manufactured by explosive bonding is widely used in the chemical industry, but cracks are often initiated in the clad layer. Repair welding is a popular method to repair the cracked zone. But residual stresses are generated inevitably, which can lead to further cracking. How to decrease the residual stress is critical to ensure the structure integrity. This paper studies a method to reduce weld residual stresses by water jet peening (WJP) in 304 stainless steel clad plate. The effect of impact pressure is discussed. A sequential coupling finite element method is developed to simulate the as-welded residual stresses, which is validated by impact indentation measurement. Then, a user subroutine is developed to model the moving load generated by WJP. The results show that the WJP can introduce compressive stresses on the metal surface and thus decrease the as-welded tensile stresses. As the maximum impact pressure at the center of impact (P0) increases, the residual stresses are decreased greatly and even change to compressive stresses. There is a critical value P0, which changes the tensile stresses to compressive stresses. As P0 increases to 1.4 times the yield strength of 304 stainless steel, the initial tensile stresses on the surface have been decreased to compressive stresses.

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Characteristics of Residual Stress by Water-Jet Peening

Materials Science Forum ◽

10.4028/www.scientific.net/msf.768-769.564 ◽

2013 ◽

Vol 768-769 ◽

pp. 564-571 ◽

Cited By ~ 1

Author(s):

Kenji Suzuki ◽

Takahisa Shobu ◽

Ayumi Shiro

Keyword(s):

Residual Stress ◽

Stress State ◽

Water Jet ◽

Biaxial Stress ◽

X Rays ◽

Lattice Plane ◽

Scanning Method ◽

Depth Direction ◽

Biaxial Stress State ◽

Specimen Material

The specimen material was austenitic stainless steel, SUS316L. The residual stress was induced by water-jet peening. The residual stress was measured using the 311 diffraction with conventional X-rays. The measured residual stress showed the equi-biaxial stress state. To investigate thermal stability of the residual stress, the specimen was aged thermally at 773 K in air to 1000 h. The residual stress kept the equi-biaxial stress state against the thermal aging. Lattice plane dependency of the residual stress induced by water-jet peening was evaluated using hard synchrotron X-rays. The residual stress measured by the soft lattice plane showed the equi-biaxial stress state, but the residual stress measured by the hard lattice plane did not. In addition, the distributions of the residual stress in the depth direction were measured using a strain scanning method with hard synchrotron X-rays and neutrons.

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Numerical Simulation of Residual Stress Field Induced by Water-Jet Cavitation Peening

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.345.312 ◽

2013 ◽

Vol 345 ◽

pp. 312-315 ◽

Cited By ~ 2

Author(s):

Bing Han ◽

Yan Hua Wang ◽

Chang Liang Xu

Keyword(s):

Numerical Simulation ◽

Residual Stress ◽

Stress Field ◽

New Technology ◽

Diffraction Method ◽

Spring Steel ◽

Water Jet ◽

Material Surface ◽

Residual Stress Field ◽

Element Analysis

Water-jet cavitation peening is a new technology for surface modification of metallic materials. Compress residual stress layer is induced by impact wave pressure in the submerged cavitating jets processing. Based on ANSYS/LS-DYNA finite element analysis software, residual stress field in the SAE1070 spring steel material surface induced by cavitate-jet water peening process is simulated, the magnitude and variation rules of the residual stress along the layer depth under different conditions is obtained. In order to verify the correctness of the numerical simulation, the size and distribution of residual stress by the X-ray diffraction method. The results show that the numerical simulation and experimental results are well consistent.

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OS1432 Development of Water Jet Peening (4) : Residual stress evaluation of WJP

The Proceedings of the Materials and Mechanics Conference ◽

10.1299/jsmemm.2009.335 ◽

2009 ◽

Vol 2009 (0) ◽

pp. 335-336

Author(s):

Hisamitsu HATOU ◽

Fujio YOSHIKUBO ◽

Nobuyoshi YANAGIDA ◽

Yoshimi SATOH ◽

Yoshihiro TOYAMA

Keyword(s):

Residual Stress ◽

Water Jet ◽

Stress Evaluation

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1028 Development and Performance Prediction of Water Jet Peening (WJP) : (4) Residual Stress Prediction Based on Bubble Collapse Energy

The Proceedings of the Materials and Mechanics Conference ◽

10.1299/jsmemm.2010.1253 ◽

2010 ◽

Vol 2010 (0) ◽

pp. 1253-1254

Author(s):

Hisamitsu HATOU ◽

Fujio YOSHIKUBO ◽

Takahiro AOKI ◽

Masashi FUKAYA

Keyword(s):

Residual Stress ◽

Performance Prediction ◽

Water Jet ◽

Bubble Collapse ◽

Stress Prediction ◽

And Performance

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Modification of Microstrucure and Residual Stress on Friction Welding Surface of Titanium Alloy by Water-Jet Cavitation Peening

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.317-319.429 ◽

2011 ◽

Vol 317-319 ◽

pp. 429-435 ◽

Cited By ~ 1

Author(s):

Dong Ying Ju ◽

Xin Mao Fu ◽

Shun Na ◽

Bing Han ◽

Xiao Hu Deng

Keyword(s):

Electron Microscopy ◽

Residual Stress ◽

Welded Joints ◽

Compressive Residual Stress ◽

Welded Joint ◽

Water Jet ◽

X Ray Diffraction ◽

X Ray ◽

Welding Surface ◽

Scanning Electron

Water jet cavitation peening is applied to improve the strength and mechanical properties of the friction-welded joints of titanium alloys. Scanning electron microscopy observations of the microstructure of the welded joints and welded area before/after water jet cavitation peening confirm slip dislocation at the microstructure near the surface of the specimens. The residual stress on the surface of the welded joint is measured by X-ray diffraction. The results indicate the effect of peening time on the strength of compressive residual stress.

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Prediction of Residual Stress Improvement by Water Jet Peening Using Cavitating Jet Simulation With Bubble Flow Model

ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting: Volume 1, Symposia – Parts A, B, and C ◽

10.1115/fedsm-icnmm2010-30419 ◽

2010 ◽

Cited By ~ 1

Author(s):

Masashi Fukaya ◽

Ren Morinaka ◽

Noboru Saitou ◽

Hisamitsu Hatou ◽

Yoshiaki Tamura ◽

...

Keyword(s):

Residual Stress ◽

Flat Plate ◽

Power Plants ◽

Compressive Residual Stress ◽

Flow Model ◽

Water Jet ◽

Bubble Collapse ◽

Bubble Flow ◽

Bubble Pressure ◽

Cavitating Jet

We developed the new method for predicting a region of compressive residual stress on the weld surface after water jet peeing (WJP), which is a preventive maintenance technology for nuclear power plants. A cavitating jet is impinged on the weld surfaces of structures in a nuclear reactor. Bubble collapse impact causes plastic deformation of the weld surface, and changes the residual stress from tensile to compressive. Compressive residual stress prevents the occurrence of stress corrosion cracking (SCC) on the weld surface. A cavitating jet vertically injected into a submerged flat plate was investigated. Tensile stress was introduced onto the surface of the stainless steel plate by grinding before WJP in the experiment. We numerically simulated impulsive bubble pressure that varied by microseconds in the cavitating jet with the “bubble flow model”. The bubble flow model simulates the abrupt time-variations in the radius and inner pressure of bubbles based on the Rayleigh-Plesset equation in a cavitating flow. The cavitation collapse energy was estimated based on the bubble pressure. The cavitation collapse energy was compared with the measured compressive residual stress on the flat plate after WJP. The radial range of the compressive residual stress from the jet center axis is one of the most important measures of performance of WJP. The radial range of the cavitation collapse energy corresponded to that of compressive residual stress with a prediction error of +/− 20% under different conditions of jet velocity and the distance between the jet nozzle and plate surface. The results confirmed that the method we developed for predicting the region of compressive residual stress after WJP was valid.

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