Piezoelectricity is a coupling between the electrical and the mechanical behaviour of certain materials, which is exploited in a wide range of transducer applications. By far most of the piezoelectric devices nowadays consist of ceramics, which are known as brittle material. Therefore, the detection of cracks in piezoelectric ceramics from external measurements in the sense of nondestructive te...

In this paper, a method for quantitatively evaluating the T " integral, directly from the measured near-tip displacement ®eld in laboratory specimens made of metallic materials, is presented for the ®rst time. Following Okada and Atluri (Okada, H., Atluri, S.N., 1999. Further studies on the characteristics of the T " integral: plane stress stable crack propagation in ductile materials. Computat...

Strain-rate effects on fracture behavior of unidirectional composite materials are studied. Single-edge notched multi-layered unidirectional graphite composites (T800/3900-2) are investigated to examine fracture responses under static and dynamic loading conditions using a digital speckle correlation method. The fracture parameters for growing cracks are extracted as a function of fiber orienta...

S E On the Fracture Toughness of Advanced Materials A R C H By Maximilien E. Launey, and Robert O. Ritchie* N E W S Few engineering materials are limited by their strength; rather they are limited by their resistance to fracture or fracture toughness. It is not by accident that most critical structures, such as bridges, ships, nuclear pressure vessels and so forth, are manufactured from materia...

Shale gas is a promising new energy source stored in shale. This research aims to study the laws of rock crack initiation and propagation under low-temperature fracturing liquid nitrogen, explore influencing factors shale reservoir effect, identify method that achieves best effect obtains highest economic benefits. Herein, visualized physical experiment nitrogen carried out, fracture process nu...

Enamel is the hardest tissue in the human body covering the crowns of teeth. Whereas the underlying dental material dentin is very well characterized in terms of mechanical and fracture properties, available data for enamel are quite limited and are apart from the most recent investigation mainly based on indentation studies. Within the current study, stable crack-growth experiments in bovine e...

Crack evaluation is essential for effective classification of pavement cracks. Digital images of pavement cracks have been analyzed using techniques such as fuzzy set theory and neural networks. Bidimensional empirical mode decomposition (BEMD), a new image analysis method recently developed, can potentially be used for pavement crack evaluation. BEMD is an extension of the empirical mode decom...