Results 231 to 240 of about 520,011 (274)

Crack tip closure and environmental crack propagation

Engineering Fracture Mechanics, 1975
Abstract Crack propagation rate, da/dN, and crack tip closure stress, σcc, in part-through crack fatigue specimens of aluminum alloys are drastically affected by gaseous environments. The present studies indicate that the crack closure reflects the influence of the environment on the plastic deformation at the crack tip, and, therefore, on the crack ...
O. Buck, J.D. Frandsen, H.L. Marcus
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Influence of crack closure in the case of an angled crack

Engineering Fracture Mechanics, 1986
Abstract This paper describes the application of super element technique to the study of crack closure phenomena in the case of an inclined crack. The influence of closure load on closure length and mode I and mode II stress intensity factors for an inclined crack are studied in detail.
S. Thiagarajan, R.S. Alwar
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Effect of crack closure on crack initiation parameters

Engineering Fracture Mechanics, 1986
Young’s modulus shear modulus elastic constant : 3 -4y plane strain ; 3 -r/l + y plane stress force per unit thickness of plate open end mode I stress intensity factor open end mode II stress intensity factor Poisson’s ratio applied uniform tension, 2p/k + 1 distance of concentrated force from centre line of crack maximum normal stress minimum strain ...
R.S. Alwar, S. Thiagarajan
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A Review of Crack Closure

1984
Abstract : A comprehensive review and critique of the literature on fatigue crack closure is presented. The elements of closure; its mechanisms, experimental procedures for its determination; the phenomenological study of its dependence on different variables, and methodologies for its prediction, are all discussed in detail.
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The relevance of crack closure to fatigue crack propagation

Materials Science and Engineering, 1974
Using the d.c. and a.c. resistance techniques it was established that for predominantly plane strain conditions, fatigue crack closure in various steels occurred only when the stress intensity conditions were reduced to below the minimum stress intensity level (KM I N) for the previous fatigue cycles.
T.C. Lindley, C.E. Richards
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Fatigue crack closure for inclined and kinked cracks

International Journal of Fracture, 2002
This paper presents recent work on finite element modelling of plasticity-induced fatigue crack closure occurring in cracks which are inclined to the loading axis, and which may then develop a kink. Such crack deviations occur naturally during crack growth, and improved life prediction models require understanding of the effects of such inclined ...
L.-W. Wei, M.N. James
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Analysis of crack-dislocation interaction: crack closure, crack opening

Materials Science and Engineering: A, 1994
Abstract The decrease in stress intensity factor, expected from dislocation emission at a crack tip, can be achieved either through a change in crack tip radius (blunting) or through a crack closure induced by the dislocation (shielding) opposite to the opening imposed by the external stress field.
M.A. Loyola de Oliveira, G. Michot
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Crack growth and closure behaviour of surface cracks

International Journal of Fatigue, 2004
Abstract This paper investigated the crack growth and closure behaviour of surface cracks in AISI 4130 alloy steel under the constant amplitude loading and single-overload conditions. The compliance measurements of depth- and surface-wise crack closure were performed using the backface strain gauge and the near-tip gauge, respectively.
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Characterization of Crack Closure

1985
Crack opening and closure levels are determined for small cracks growing from sharp and blunt notches during cyclic loading. Crack tip opening displacement measurements as low as 0.1 μm are reported. Experimental crack opening levels are compared with analytical crack opening levels for various stress intensity ranges, crack lengths, and R-ratios.
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Some experimental observations on crack closure and crack‐tip plasticity

Fatigue & Fracture of Engineering Materials & Structures, 2009
ABSTRACTThis study presents a methodology for evaluating crack closure and the effect of crack‐tip plasticity on stress intensity. Full‐field displacement maps obtained by digital image correlation are used to obtain the mixed‐mode, crack‐driving force.
Lopez-Crespo, P, Shterenlikht, A, Yates, JR, Patterson, EA, Withers, PJ   +4 more
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