• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.10
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• pp.27-33
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• 2003

A method for the retardation of fatigue crack growth using ring indentation at the vicinity of a crack is examined. Residual stresses near crack tip are evaluated using fracture mechanics approach using the Bueckner weight function. The motivation is to develop a simple and effective method for obtaining an increase in fatigue lives to total failure of materials with crack. Fatigue testing of aluminum specimen showed that the retardation effects are observed after the application of the method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.1
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• pp.130-137
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• 1990

Thermal shock stress intensity factor for an edge-cracked plate subjected to thermal shock is obtained from Bueckner's weight function method. It is shown that thermal shock stress intensity factor has maximum values with variation of time and crack length and that there is most dangerous crack length. By comparing thermal shock stress intensity factor with fracture toughness, the fracture time and critical temperature difference due to thermal shock are determined theoretically. Under constant thermal shock temperature difference, and increase of crack length is shown to increase fracture time. The theoretical fracture time is compared with experimental value measured by acoustic emission method with soda lime glass.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.7
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• pp.208-216
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• 2003

In this paper, a two-dimensional electroelastic analysis is performed on a piezoelectric material with an open crack. The approach of Lekhnitskii's complex potential functions is used in the derivation and Bueckner's weight function theory is extended to piezoelectric materials. The stress intensity factors and the electric displacement intensity factor are calculated by the weight function theory.

• Journal of Ocean Engineering and Technology
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• v.24 no.3
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• pp.59-63
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• 2010

In this paper, an electroelastic analysis is performed on a piezoelectric material with an open crack in anti-plane deformation. Bueckner’s weight function theory is extended to piezoelectric materials in anti-plane deformation. The stress intensity factors and electric displacement intensity factor are calculated by the weight function theory.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.1
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• pp.7-11
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• 2017

In this study, we develop the exact field of mode I in an infinitely deep crack in a half-plane. Using this field, we obtain the exact stress intensity factor $K_{I}$. From the tractions on the crack faces induced by exact field, we calculate the stress intensity factor of this field. We compare the results with the stress intensity factor calculated using Bueckner's weight function formula and that calculated by using Tada's formula listed in "The Stress Analysis of Cracks Handbook" It was found that Bueckner's formula yields accurate results. However, the results obtained using Tada's formula exhibit inaccurate behavior.