Fatigue crack growth and closure behaviour through a compressive residual stress fieldKang, K.J., Song, J.H. and Earmme, Y.Y. Fatigue Fract. Eng. Mater. Struct. 1990 13 (1), 1–13

This study evaluated fatigue crack growth characteristics, Besides consider compressive residual stress effect and verified the most suitable shot peening velocity. Fatigue crack growth delay effect was compressive residual stress, but over peening did action projecting velocity that accelerate fatigue crack growth rate. X-ray diffraction technique according to crack length direction was applied to fatigue fractured surface. Fracture mechanics parameters could be estimated by the measurement of X-ray parameters, and the fractography observation was performed using a scanning electron microscope (SEM) for fatigue fracture surface. As the shot peening velocity increases, striation width increased. The changes in X-ray material parameters described above are directly related to the process of fatigue until the initiation of fatigue crack and X-ray diffraction pattern is thought that failure prediction with stress distribution is possible.

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Investigation on Fatigue Crack Growth Behaviour in S45C Steel by Water Cavitation Peening with Aeration

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.2485 ◽

2007 ◽

Vol 561-565 ◽

pp. 2485-2488 ◽

Cited By ~ 6

Author(s):

B. Han ◽

Dong Ying Ju ◽

Tetsuya Nemoto

Keyword(s):

Residual Stress ◽

Surface Layer ◽

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Compressive Residual Stress ◽

Bubble Collapse ◽

In Situ Observation ◽

Crack Growth Behaviour ◽

Near Surface

Water cavitation peening (WCP) with aeration is a recent promising method in the surface enhancement technique, which can induce compressive residual stress in the near surface of mechanical components by the bubble collapse on the surface of components in the similar way as conventional shot peening. In this paper, the effect of WCP on fatigue crack growth behavior was investigated in single-edge-notched flat tensile specimens of S45C steel. The notched specimens were treated by WCP, and the compressive residual stress distributions in the near surface layer were measured by X-ray diffraction method. The tension-tension (R = Smin/Smax = 0.1, f = 10 Hz) fatigue tests were conducted. A Shimadzu servo-hydraulic fatigue test machine with in-situ observation by JSM-5410LV scanning microscope was used for all testing. Compared with those without WCP treatment, WCP can induce the residual compressive stress in the near surface layer, and delay the fatigue crack initiation, and decrease the rate of fatigue crack growth.

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Suppression of Fatigue Crack Growth in Austenite Stainless Steel by Cavitation Peening

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.452-453.641 ◽

2010 ◽

Vol 452-453 ◽

pp. 641-644 ◽

Cited By ~ 1

Author(s):

Osamu Takakuwa ◽

Masaaki Nishikawa ◽

Hitoshi Soyama

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Surface Modification ◽

Fatigue Crack ◽

Fatigue Strength ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Compressive Residual Stress ◽

Austenite Stainless Steel ◽

The Impact

Cavitation normally causes severe damage in hydraulic machinery such as pumps and turbines by the impact produced by cavitation bubbles collapsing. Although cavitation is known as a factor of erosion, Soyama et al. succeeded in utilizing impacts of cavitation bubble collapsing for surface modification by controlling cavitating jet in the same way as shot peening. The local plastic deformation caused by cavitation impact enhances the fatigue strength of metallic materials, and the surface modification technique utilizing cavitation impact is called “cavitation peening (CP)”. It is well known that the peening improves fatigue strength by introducing compressive residual stress on the surface, but little attention has been paid to the behavior of fatigue crack growth of the material which was modified by CP. In the present study, the fatigue behavior of austenite stainless steel with and without CP was evaluated by a plate bending fatigue test, and the results revealed that the compressive residual stress introduced by CP suppresses fatigue crack growth rate by 70 % compared to that without CP.

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