Sol–gel Ru0.3Sn0.7O2 electrode coatings with crack-free and mud-crack surface morphology deposited onto a Ti-substrate are prepared for a comparative investigation of the microstructural effect on the electrochemical activity for Cl2 production and the Cl2 bubble evolution behaviour. For comparison, a state-of-the-art mud-crack commercial Ru0.3Ti0.7O2 coating is used. The compact coating is pot...

This paper considers a 2-D fracture analysis of anisotropic piezoelectric solids by a boundary elementfree method. A traction boundary integral equation (BIE) that only involves the singular terms of order 1/r is first derived using integration by parts. New variables, namely, the tangential derivative of the extended displacement (the extended displacement density) for the general boundary and...

A.N. Norris and J.D. Achenbach The Technological Institute Northwestern University Evanston, IL 60201 Crack diffraction in a transversely isotropic material is analyzed. The solution is given for the diffracted field generated by incidence of a plane time-harmonic wave on a semiinfinite crack located in a plane normal to the axis of symmetry of the material. The exact solution is obtained by Fo...

A number of researchers are attempting to develop a biosensor based on terahertz sensing. Key to the realization of any biosensor system is the access of the target molecules to the sensor. In the case of using terahertz spectroscopy, there are limitations due to high attenuation by water and sensitivity levels. In order to have a significant response at THz frequencies generally requires a min...

The energy balance associated with the transmission of cleavage front across high angle grain boundary is analysed theoretically. On the one hand, if the distance between adjacent breakthrough points is small, their crack trapping effect tends to be pronounced. On the other hand, decreasing this distance promotes the separation of persistent grain boundary areas. The effective grain boundary to...

Sol-gel Ru(0.3)Sn(0.7)O(2) electrode coatings with crack-free and mud-crack surface morphology deposited onto a Ti-substrate are prepared for a comparative investigation of the microstructural effect on the electrochemical activity for Cl(2) production and the Cl(2) bubble evolution behaviour. For comparison, a state-of-the-art mud-crack commercial Ru(0.3)Ti(0.7)O(2) coating is used. The compac...

Delamination of coatings initiated by small cracks paralleling the free surface is investigated under conditions of high thermal flux associated with a through-thickness temperature gradient. A crack disrupts the heat flow thereby inducing crack tip stress intensities that can become critical. A complete parametric dependence of the energy release rate and mode mix is presented in terms of the ...

The application of a coupled ®nite element± element-free Galerkin (EFG) method to problems in threedimensional fracture is presented. The EFG method is based on moving least square (MLS) approximations and uses only a set of nodal points and a CAD-like description of the body to formulate the discrete model. The EFG method is coupled with the ®nite element method which allows for the use of the...

An asymptotic description of the acoustic signature of a crack, breaking the surface of an otherwise homogeneous, isotropic elastic material, determined using either a line focus or a point focus scanning acoustic microscope is constructed. The incident focused beam is constructed as a Fourier integral that produces a specified profile in the focal plane. The wavefields scattered from the speci...

This paper describes a method for determining the depth of machined slots simulating cracks by the use of Rayleigh waves. Six slots varying in depth from 0.5 mm to 3.0 mm fabricated in medium carbon steel have been sized using a commercially available 1.5 MHz Rayleigh wave transducer. One measurement using the pulse-echo method is made for determining the depth of the crack. Minima in the decon...