Channeling cracks in brittle thin films have been observed to be a key reliability issue for advanced interconnects and other integrated structures. Most theoretical studies to date have assumed no delamination at the interface, while experiments have observed channel cracks both with and without interfacial delamination. This paper analyzes the effect of interfacial delamination on the fractur...

a crack depth in mm, same as x â measurement system response, 1 – R– A(x) system model for evolving crack depth x A(n) linearised system model at measurement set n B(x) measurement model giving normalised energy ratio R– as a function of crack depth x B(n) linearised measurement model at measurement set n B(R) inverse measurement model giving crack depth x as a function of normalised energy rat...

The role of crack-tip shielding in in ̄uencing mixed-mode (mode I‡ II) fatigue-crack growth thresholds for large, through-thickness cracks in a Ti±6Al±4V turbine blade alloy is examined under high-cycle fatigue loading conditions, i.e., at a loading frequency of 1000 Hz in ambient temperature air for load ratios (Kmin=Kmax) of R ˆ 0:1±0.8. Techniques are developed to quantify crack-tip shielding...

An understanding of the evolution of toughness is essential for the mechanistic interpretation of the fracture of cortical bone. In the present study, in vitro fracture experiments were conducted on human cortical bone in order to identify and quantitatively assess the salient toughening mechanisms. The fracture toughness was found to rise linearly with crack extension (i.e., rising resistance-...

Although the propagation of fatigue cracks has been recognized as a problem of clinical significance in dentin, there have been few fracture mechanics-based studies that have investigated this issue. In the present study, in vitro cyclic fatigue experiments were conducted over a range of cyclic frequencies (1-50 Hz) on elephant dentin in order to quantify fatigue-crack growth behavior from the ...

Quasi-static shear crack propagation in a linear elastic fluid-saturated porous solid c;Iuses a change of pore pressure on the crack plane if it is impermeable but not if it is permeable. Assuming that the pore pressure induced on the crack plane reduces the efTcclive compressive stress (total stress minus pore fluid pressure) and. as a result. the frictional resistance. we find that the energy...

In this study, the crack growth behavior in a filled elastomer, containing hard particles embedded in a rubbery matrix, was investigated. The specimen was tested at a constant strain rate of 0.067 cm/cm/min at room temperature. Two initial crack lengths, 2.54 mm and 12.7 mm, were considered. A hybrid experimental-numerical method was used to calculate the Jintegral value. They also revealed tha...

In previous work, fatigue-crack-growth tests were conducted on middle-crack tension, M(T), and compact, C(T), specimens made from the same D16Cz (clad) aluminum alloy sheet. These tests were conducted over a wide range of stress ratios (R = Pmin/Pmax = 0.5 to 0.75) to generate crack-growth-rate data from threshold to near fracture. These tests were used to generate the effective stress-intensit...

It is necessary to manage the fatigue crack growth (FCG) once those cracks are detected during in-service inspections. In this paper, a simulation program (FCG-System) is developed utilizing the commercial software ABAQUS with its object-oriented programming interface to simulate the fatigue crack path and to compute the corresponding fatigue life. In order to apply FCG-System in large-scale ma...