Download or read book Acoustic Emission Determination of Deformation Mechanisms Leading to Failure of Naval Alloys Phase I written by J. T. Glass and published by . This book was released on 1981 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the present research is to use innovative optical techniques and superior signal capture and processing systems to determine the waveforms, frequency spectra, and propagational behavior of the acoustic emission signals generated by the various mechanical deformation mechanisms leading to failure of metal alloys of prime importance to naval structures. The ultimate goal of this research is to absolutely determine the degree to which precise characterization of the acoustic emission signals can serve to remotely assess the severity of mechanical damage and give early warning of impending failure. Experiments were performed using a modified piezoelectric transducer, a Fizeau type interferometer, and a modified Michelson interferometer. Acoustic emission events were generated by pulling microtensile specimens in an extremely quiet microtensile machine and by the brittle, step unloading fracture of glass capillary tubes on the surface of test specimens possessing different geometries. All acoustic emission event waveforms were recorded by a high speed transient recorder and stored on magnetic mini-diskettes for analysis on a high speed digital computer and for future propagational behavior and waveform analysis. Specimens which were pulled on the microtensile machine were examined under optical and scanning electron microscopes to determine a point by point correlation between acoustic emission events and microstructural changes.

Download or read book Acoustic Emission Determination of Deformation Mechanisms Leading to Failure of Naval Alloys written by J. T. Glass and published by . This book was released on 1983 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: IN this investigation the acoustic emission behavior of three Naval alloy steels (HY 80, HY 100 and HY 130) was characterized during tensile elongation and bend type loading. The detection of emissions was accomplished using a very new, state of the art interferometer as well as with a unique piezoelectric transducer. The deformation and fracture of these HY steels was documented via optical and scanning electron microscopy and was correlated with observed emissions in order to determine the generating mechanisms. All three steels investigated were found to exhibit very similar deformation and fracture modes despite a slight difference in microstructures. They also exhibited identical acoustic emission behavior within statistical variances. Their fracture consisted of a very ductile mode involving void coalescence and growth with final failure occurring by knife edge rupture of numerous microligaments between voids. Two major types of acoustic emission were detected. The first occurred prior to yielding and was attributed to dislocation glide over distances above some critical minimum detectable mean free path.

Download or read book Acoustic Emission Determination of Deformation Mechanisms Leading to Failure of Naval Alloys written by J. T. Glass and published by . This book was released on 1983 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation was conducted in order to determine the degree of acoustic emission signal modification due to propagation through specimens of different geometries. Initial efforts were directed at comparison of a number of acoustic emission probes in order to determine their sensitivity and their ability to detect an unmodified reproducible theoretically predicted waveform. The results of these tests showed that an optical interferometric probe possessed the largest frequency bandwidth and a National Bureau of Standards conical piezoelectric transducer possessed the best waveform detection sensitivity. These two probes were therefore selected to make measurements of the surface displacements due to a reproducible acoustic emission source as a function of distance from the source for several different geometrically shaped objects. Long test specimens in the form of a right circular cylinder, a rectangular cross-section bar, a moderately thin-walled pipe, and an I-beam were used for these propagation measurements.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nondestructive Monitoring of Materials Properties Volume 142 written by John Holbrook and published by Mrs Proceedings. This book was released on 1989-11-20 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.

Download or read book The Shock and Vibration Digest written by and published by . This book was released on 1984 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1984 with total page 906 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Abstract Bulletin written by Defense Documentation Center (U.S.) and published by . This book was released on 1963 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Journal of Acoustic Emission written by and published by . This book was released on 1994 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metals Abstracts written by and published by . This book was released on 1993 with total page 1220 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Alloys Index written by and published by . This book was released on 1990 with total page 1040 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Navy Vehicles Acoustic Emission Related to Nondestructive Testing written by Kanji Ono and published by . This book was released on 1988 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: This investigation was aimed at studying acoustic emission for applications to residual stress measurements and for the evaluation of structural integrity of engineering structures. Effects of microstructure, composition and prior cold working on magnetomechanical acoustic emission(MAE) have been studied. Magnetization behavior, magnetostriction and Barkhausen noise are affected by stress as well as other parameters. These responses have been measured simultaneously in order to identify the stress level uniquely. Combinations of advanced signal analysis methods and MAE measurements have been studied to identify the optimum parameters for applications. This work has established mechanisms of MAE signal generation, effects of various parameters that influence the MAE behavior of materials and signal processing techniques that allow materials characterization via MAE. Included are neutron irradiated reactor vessel steels, large size steel plates as well as single crystals of various ferromagnetic metals and alloys. In the second part of this study, acoustic emission from materials undergoing plastic deformation and fracture have been examined in an attempt to improve detection capability of the impending structural failure. Acoustic emission characteristics of reactor vessel steels, advanced aluminum alloys and metal and ceramic matrix composite materials have been evaluated in detail. Keywords: Nondestructive testing; Test and Evaluation; Naval equipment; Reprints.

Download or read book Acoustic Emission During the Deformation and Fracture of Three Naval Alloy Steels written by Jeffrey Taylor Glass and published by . This book was released on 1983 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Annual Review of Materials Science written by Robert A. Huggins and published by . This book was released on 1990 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1984 with total page 1300 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index Keyword A L written by and published by . This book was released on 1987 with total page 1060 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Acoustic Emission Produced by Deformation of Metals and Alloys written by C. R. Heiple and published by . This book was released on 1987 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: