Critical Thoughts on Structural Mechanics and Nde

摘要

A critical review of non-destructive evaluation (NDE) is given in general terms and specific examples of NDE techniques are given. These employ radiography (X-ray and neutron), ultrasonics, penetrants, eddy currents, thermography, laser interferometry and holography. Other techniques not discussed in detail include magnetics, Mossbauer spectra, and spin resonance. The state-of-the-art is presently technique-oriented, rather than problem oriented due, in part, to ineffective communication links between designer, NDE researcher and user. Problems areas are identified which include better data handling and interpretive techniques for the user as well as detectability and resolution criteria; and certain materials problems (e.g., limited ductility materials); and an especially urgent need is expressed for control indices for surface contamination by NDE. Methods are suggested for improving the communications link and the idea of 'analogue' acceptability or evaluation is stressed in favor of 'binary' go:no-go type decisions. In this way the NDE techniques would enjoy more user acceptance as well as utility. (Author)