The stress intensity factor history for an advancing crack in a transversely isotropic solid under 3-D loading

The stress distribution produced by the identation of a penny-shaped crack by an oblate smooth spheroidal rigid inclusion in a transversely isotropic medium is investigated using the method of Hankel transforms. This three-part mixed boundary value problem is solved using the techniques of triple integral equations. The normal contact stress between the crack surface and the indenter is written as the product of the associated half-space contact stress and a nondimensional crack-effect correction function. An exact expression for the stress-intensity is obtained as the product of a dimensional quantity and a nondimensional function. The curves for these nondimensional functions are presented and used to determine the values of the normalized stress-intensity factor and the normalized maximum contact stress. The stress-intensity factor is shown to be dependent on the material constants and increasing with increasing indentation. The stress-intensity factor also increases if the radius of curvature of the indenter surface increases.

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Dynamic Response to Normal Stresses in a Transversely Isotropic Material Containing an External Circular Crack

Journal of Engineering Materials and Technology ◽

10.1115/1.2904163 ◽

1992 ◽

Vol 114 (2) ◽

pp. 208-212 ◽

Cited By ~ 2

Author(s):

Y. M. Tsai

Keyword(s):

Stress Intensity Factor ◽

Stress Intensity ◽

Intensity Factor ◽

Isotropic Material ◽

Dynamic Stress ◽

Dynamic Stress Intensity Factor ◽

Circular Crack ◽

Transversely Isotropic ◽

Transversely Isotropic Material ◽

External Circular Crack

The dynamic response of an external circular crack to a harmonic longitudinal wave in a transversely isotropic material is investigated using the techniques of Hankel transform. The wave impinges normally onto the crack surfaces. The inversion integral is evaluated and simplified through a complete contour integration. An exact expression for the dynamic stress intensity factor is obtained in terms of the wave frequency and the anisotropic material constants. The maximum value of the normalized dynamic stress-intensity factor is shown to occur at different wave frequencies for different sample composite and metallic materials. The dynamic effect on the crack surface displacement is also shown to be a function of the wave frequency and the material anisotropy.

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Torsional Vibration of an External Circular Crack in a Transversely Isotropic Composite

Engineering Technology Conference on Energy, Parts A and B ◽

10.1115/etce2002/cmda-29078 ◽

2002 ◽

Author(s):

Y. M. Tsai

Keyword(s):

Stress Intensity Factor ◽

Stress Intensity ◽

Intensity Factor ◽

Dynamic Stress ◽

Dynamic Stress Intensity Factor ◽

Circular Crack ◽

Transversely Isotropic ◽

Dynamic Crack ◽

Isotropic Composite ◽

External Circular Crack

The forced torsional vibratory motion of an external circular crack in a transversely isotropic composite is investigated by using the method of Hankel transforms. A pair of vibratory torques of equal amplitude is applied at infinity. The infinite integral involved is evaluated through a contour integration to be discontinuous in nature. An exact expression for the dynamic stress intensity factor is obtained in terms of the frequency factor and the anisotropic material constants. The maximum value of the normalized dynamic stress-intensity factor is shown to occur at different frequency factors for the sample fiber-reinforced and metal matrix composites. The distortion of the dynamic crack surface displacement from the associated static displacement depends also on the forcing frequency and the material anisotropy.

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