Strain and Stress Analysis by Holographic and Speckle Interferometry

Abstract

The first chapter of this book provides an introduction to optical holography and speckle interferometry. While the explanation is sound and thorough it lacks clarity and it is doubtful that it will be understood by any reader who is not an expert in modern optics. The second and third chapters are devoted, respectively, to holographic interferometry and speckle interferometry. The treatment of both topics is rigorous, there are good discussions of experimental errors and experimental techniques and comprehensive bibliographies. Holographic and speckle interferometry, unlike Moirè, do not require any special surface preparation and dispense with the use of gratings, but the fringe patterns produced are difficult to interpret. The mapping out of the displacement field from the experimental data and the derivation of strains are discussed in chapter 4, where the problem presented by steep changes in displacement near strain raisers is addressed. While mathematical techniques for differentiation of experimental data are presented, no mention is made of modern computer software used to automate the process. More than half of the book consists of a number of examples from many different fields: shell structures, fracture mechanics, low cycle fatigue, contact problems, residual stress measurements by the hole drilling method and other practical cases. These examples are taken from the Russian scientific literature. Apart from their interest to the specialist, they illustrate experimental techniques not commonly used in the western world. C Ruiz