Effect of residual stresses on interface crack growth by void expansion mechanism

Some fatigue crack growth data have been obtained for age-hardened beryllium copper. The fatigue crack growth rate was found to be very dependent on the hardness and tensile mean stress. This dependence is believed to be associated with the intense residual stresses surrounding Preston-Guinier zones.

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Failure Mechanisms of Particulate Two-Phase Composites

MRS Proceedings ◽

10.1557/proc-529-151 ◽

1998 ◽

Vol 529 ◽

Author(s):

T. Antretter ◽

E D. Fischer

Keyword(s):

Residual Stresses ◽

Crack Growth ◽

Opening Angle ◽

Geometrical Parameters ◽

Two Phase ◽

Absolute Size ◽

The Matrix ◽

Unit Cells ◽

Angle Criterion ◽

Probability Of Fracture

AbstractIn many composites consisting of hard and brittle inclusions embedded in a ductile matrix failure can be attributed to particle cleavage followed by ductile crack growth in the matrix. Both mechanisms are significantly sensitive towards the presence of residual stresses.On the one hand particle failure depends on the stress distribution inside the inclusion, which, in turn, is a function of various geometrical parameters such as the aspect ratio and the position relative to adjacent particles as well as the external load. On the other hand it has been observed that the absolute size of each particle plays a role as well and will, therefore, be taken into account in this work by means of the Weibull theory. Unit cells containing a number of quasi-randomly oriented elliptical inclusions serve as the basis for the finite element calculations. The numerical results are then correlated to the geometrical parameters defining the inclusions. The probability of fracture has been evaluated for a large number of inclusions and plotted versus the particle size. The parameters of the fitting curves to the resulting data points depend on the choice of the Weibull parameters.A crack tip opening angle criterion (CTOA) is used to describe crack growth in the matrix emanating from a broken particle. It turns out that the crack resistance of the matrix largely depends on the distance from an adjacent particle. Residual stresses due to quenching of the material tend to reduce the risk of particle cleavage but promote crack propagation in the matrix.

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Slow Crack Growth in Glasses and Ceramics Under Residual and Applied Stresses

Journal of Electronic Packaging ◽

10.1115/1.3226510 ◽

1989 ◽

Vol 111 (1) ◽

pp. 61-67 ◽

Cited By ~ 3

Author(s):

F. Erdogan

Keyword(s):

Stress Intensity Factor ◽

Stress Intensity ◽

Intensity Factor ◽

Residual Stresses ◽

Crack Growth ◽

Slow Crack Growth ◽

Threshold Value ◽

Crack Arrest ◽

Growing Crack ◽

Applied Stresses

The problem of slow crack growth under residual stresses and externally applied loads in plates is considered. Even though the technique developed to treat the problem is quite general, in the solution given it is assumed that the plate contains a surface crack and the residual stresses are compressive near and at the surfaces and tensile in the interior. The crack would start growing subcritically when the stress intensity factor exceeds a threshold value. Initially the crack faces near the plate surface would remain closed. A crack-contact problem would, therefore, have to be solved to calculate the stress intensity factor. Depending on the relative magnitudes of the residual and applied stresses and the threshold and critical stress intensity factors, the subcritically growing crack would either be arrested or become unstable. The problem is solved and examples showing the time to crack arrest or failure are discussed.

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Weld Residual Stresses and Primary Water Stress Corrosion Cracking in Bimetal Nuclear Pipe Welds

Volume 6: Materials and Fabrication ◽

10.1115/pvp2007-26297 ◽

2007 ◽

Cited By ~ 11

Author(s):

Frederick W. Brust ◽

Paul M. Scott

Keyword(s):

Water Stress ◽

Residual Stresses ◽

Weld Metal ◽

Stress Corrosion ◽

Crack Growth ◽

Stress Corrosion Cracking ◽

Pressure Vessel ◽

Large Diameter ◽

Corrosion Cracking ◽

Primary Water

There have been incidents recently where cracking has been observed in the bi-metallic welds that join the hot leg to the reactor pressure vessel nozzle. The hot leg pipes are typically large diameter, thick wall pipes. Typically, an inconel weld metal is used to join the ferritic pressure vessel steel to the stainless steel pipe. The cracking, mainly confined to the inconel weld metal, is caused by corrosion mechanisms. Tensile weld residual stresses, in addition to service loads, contribute to PWSCC (Primary Water Stress Corrosion Cracking) crack growth. In addition to the large diameter hot leg pipe, cracking in other piping components of different sizes has been observed. For instance, surge lines and spray line cracking has been observed that has been attributed to this degradation mechanism. Here we present some models which are used to predict the PWSCC behavior in nuclear piping. This includes weld model solutions of bimetal pipe welds along with an example calculation of PWSCC crack growth in a hot leg. Risk based considerations are also discussed.

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Effect of Anisotropic Plasticity on Mixed Mode Interface Crack Growth

Fracture of Nano and Engineering Materials and Structures ◽

10.1007/1-4020-4972-2_484 ◽

2008 ◽

pp. 977-978

Author(s):

V. Tvergaard ◽

B. N. Legarth

Keyword(s):

Crack Growth ◽

Interface Crack ◽

Mixed Mode ◽

Anisotropic Plasticity

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Influence of Weld Residual Stresses on Ductile Crack Behavior in AISI Type 316LN Stainless Steel Weld Joint

Volume 3B: Design and Analysis ◽

10.1115/pvp2018-84693 ◽

2018 ◽

Author(s):

Sai Deepak Namburu ◽

Lakshmana Rao Chebolu ◽

A. Krishnan Subramanian ◽

Raghu Prakash ◽

Sasikala Gomathy

Keyword(s):

Residual Stress ◽

Residual Stresses ◽

Crack Growth ◽

Weld Joint ◽

Volume Fraction ◽

Growth Behavior ◽

Welding Residual Stress ◽

Crack Growth Behavior ◽

Ductile Crack ◽

Ductile Crack Growth

Welding residual stress is one of the main concerns in the process of fabrication and operation because of failures in welded steel joints due to its potential effect on structural integrity. This work focuses on the effect of welding residual stress on the ductile crack growth behavior in AISI 316LN welded CT specimens. Two-dimensional plane strain model has been used to simulate the CT specimen. X-ray diffraction technique is used to obtain residual stress value at the SS 316LN weld joint. The GTN model has been employed to estimate the ductile crack growth behavior in the CT-specimen. Results show that residual stresses influence the ductile crack growth behavior. The effect of residual stress has also been investigated for cases with different initial void volume fraction, crack lengths.

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