Shrinkage behavior and crack formation during firing have been investigated for Al2O3/Ce-TZP composites that have been fabricated by colloidal rolling and folding. These composites show improved sinterability and sinter isotropically after repeated rolling. Interface instability in rolling creates corrugated interfaces with large layer waviness; therefore, rolling can substantially alleviate th...

The paper concerns the validation of a method for solving elastodynamics problems for cracked solids. The proposed method is based on the application of boundary integral equations. The problem of an interface penny-shaped crack between two dissimilar elastic half-spaces under harmonic loading is considered as an example.

Vibrothermography often employs a high-power actuator to generate heat on a specimen to reveal damage, however, the high-power actuator brings inconvenience to the application and possibly introduces additional damage to the inspected objects. This study uses a low-power piezoceramic transducer as the actuator of vibrothermography and explores its ability to detect multiple surface cracks in a ...

Partition of unity enrichment techniques are developed for bimaterial interface cracks. A discontinuous function and the two-dimensional near-tip asymptotic displacement functions are added to the finite element approximation using the framework of partition of unity. This enables the domain to be modelled by finite elements without explicitly meshing the crack surfaces. The crack-tip enrichmen...

The development of vertical cracks in air plasma sprayed (APS) thermal barrier coatings (TBCs) during cycling and constrained sintering under a temperature gradient is investigated. Microstructural analysis shows that the associated with multiple processes, including hold period cleavage cooldown. Inspired by experimental observations, an image-based model used to simulate as coating sinters wh...

A copper/Q235 steel/copper composite block with excellent bonding interfaces was prepared by explosive welding which a promising technique to fabricate laminates. The microstructure and mechanical properties of the were investigated via tensile-shear test, optical microscope (OM), X-ray diffraction (XRD), scanning electron (SEM), back-scattered (EBSD). results showed that shear strength upper-i...

Cracks often arise in an aeroengine labyrinth disc, which endanger flight security. Non-destructive testing (NDT) must been carried out in the labyrinth disc during the aeroengine working time. In situ detecting cracks in the labyrinth disc, the probe need pass through three layers narrow holes of aircraft skin, engine shell and outlet duct. Ultrasonic, radiography and liquid penetrant inspecti...

The ®nite element alternating method is extended further for analyzing multiple arbitrarily curved cracks in an isotropic plate under plane stress loading. The required analytical solution for an arbitrarily curved crack in an in®nite isotropic plate is obtained by solving the integral equations formulated by Cheung and Chen (1987a, b). With the proposed method several example problems are solv...

A study is made of veneer failure by cracking in all-ceramic crown-like layer structures. Model trilayers consisting of a 1 mm thick external glass layer (veneer) joined to a 0.5 mm thick inner stiff and hard ceramic support layer (core) by epoxy bonding or by fusion are fabricated for testing. The resulting bilayers are then glued to a thick compliant polycarbonate slab to simulate a dentin ba...