Prediction of crack growth initiation in paper structures using a J-integral criterion

Abstract 1. Evaluation of ∫σdδ where σ is the net section stress and δ is the deformed crack tip diameter requires only one specimen to characterize the initiation of crack growth in unfilled and carbon-black-filled NR. 2. ∫σdδ is equal to one half of the J-integral for crack growth initiation, which is identical to the Thomas tearing energy for a blunt notch. 3. The critical J-integral for crack initiation increases linearly with carbon black content. 4. The critical crack tip radius for crack initiation is independent of carbon black content, and the required crack tip region stress increases linearly with carbon black content.

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Hybrid Experimental-Numerical J-Integral Analysis and Crack Growth Resistance of a Particulate Composite Material

10.21236/ada410488 ◽

2001 ◽

Author(s):

C. T. Liu ◽

Javier Gonzalez

Keyword(s):

Composite Material ◽

Crack Growth ◽

Particulate Composite ◽

Crack Growth Resistance ◽

J Integral ◽

Integral Analysis ◽

Particulate Composite Material

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Fracture and Fatigue Resistance of Ultrafine Grain CuCrZr Alloy Produced ECAP

Materials Science Forum ◽

10.4028/www.scientific.net/msf.503-504.811 ◽

2006 ◽

Vol 503-504 ◽

pp. 811-816 ◽

Cited By ~ 12

Author(s):

Alexei Vinogradov ◽

Kazuo Kitagawa ◽

V.I. Kopylov

Keyword(s):

Growth Rate ◽

Crack Growth Rate ◽

Crack Growth ◽

Stable Crack Growth ◽

Ultrafine Grain ◽

J Integral ◽

Present Communication ◽

Angular Pressing ◽

Fatigue And Fracture ◽

Anisotropy Of Mechanical Properties

Anisotropy of mechanical properties, fatigue and fracture resistance of precipitation hardened CuCrZr alloy ultrafine (UFG) grained by equal-channel angular pressing (ECAP) is in focus of the present communication. Fracture toughness was estimated in terms of J-integral and the fatigue crack growth rate was quantified. It was found that although the estimated JIC-value appeared lower than that reported in the literature for a reference alloy, the ductility, fracture and crack growth resistance remained satisfactory after ECAP while the tensile strength and fatigue limit improved considerably. The stable crack growth rate did not differ very much for ECAP and reference conventional CuCrZr and no remarkable anisotropy in the stable crack growth was noticed.

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Advantageous Description of Short Fatigue Crack Growth Rates in Austenitic Stainless Steels with Distinct Properties

Metals ◽

10.3390/met11030475 ◽

2021 ◽

Vol 11 (3) ◽

pp. 475

Author(s):

Lukáš Trávníček ◽

Ivo Kuběna ◽

Veronika Mazánová ◽

Tomáš Vojtek ◽

Jaroslav Polák ◽

...

Keyword(s):

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Stainless Steels ◽

Growth Rates ◽

Large Scale ◽

J Integral ◽

Scale Yielding ◽

Residual Fatigue ◽

Crack Growth Rates

In this work two approaches to the description of short fatigue crack growth rate under large-scale yielding condition were comprehensively tested: (i) plastic component of the J-integral and (ii) Polák model of crack propagation. The ability to predict residual fatigue life of bodies with short initial cracks was studied for stainless steels Sanicro 25 and 304L. Despite their coarse microstructure and very different cyclic stress–strain response, the employed continuum mechanics models were found to give satisfactory results. Finite element modeling was used to determine the J-integrals and to simulate the evolution of crack front shapes, which corresponded to the real cracks observed on the fracture surfaces of the specimens. Residual fatigue lives estimated by these models were in good agreement with the number of cycles to failure of individual test specimens strained at various total strain amplitudes. Moreover, the crack growth rates of both investigated materials fell onto the same curve that was previously obtained for other steels with different properties. Such a “master curve” was achieved using the plastic part of J-integral and it has the potential of being an advantageous tool to model the fatigue crack propagation under large-scale yielding regime without a need of any additional experimental data.

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