Download or read book Correlation of Acoustic Emission Generated During Uniform Biaxial Loading to Microstructural Sources in 7075 T651 Aluminum and 21Cr 6Ni 9Mn Stainless Steel Final Report written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper reports on the effect on acoustic emission (AE) of uniform biaxial loading of a thin-walled tube designed by Hamstad, Patterson and Mukherjee. The AE generated during biaxial loading of 7075-T651 aluminum and 21Cr-6Ni-9Mn stainless steel had several anomalous features relative to tensile generated AE. The biaxial AE data was of a much higher level and peaked at a lower strain than the uniaxial AE response. A particle cracking model was proposed in which inclusions with the largest projected surface area perpendicular to the principal axis of applied loading will crack before smaller inclusions, and the resulting energy released per AE will be proportional to the crack surface area. The inclusion contents were studied with respect to size, shape, density, hardness, and fracture/decohesion behavior. The inclusions in both 7075-T651 and 21-6-9 display the preferred cracking orientation predicted in the Hamstad, et al. model and are shown to be associated with the generated AE. However, other factors appear to contribute to the total AE responses. There is evidence that for 7075-T651 subjected to biaxial loading, a grain boundary-related mechanism becomes a significant source of AE in the latter stages of strain hardening. Also, for both materials, the complex applied load during biaxial loading appears to amplify the level of AE.
Download or read book On the Correlation of Acoustic Emission Generated During Uniform Biaxial Loading to Microstructural Sources in 7075 T651 Aluminum and 21Cr 6Ni 9Mn Stainless Steel written by Edward Michael Leon and published by . This book was released on 1981 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1982 with total page 1696 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1982 with total page 1282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1982 with total page 844 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 1982 with total page 692 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 1982 with total page 838 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 1982 with total page 1018 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 1983-07 with total page 1250 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 1982 with total page 1016 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 1983 with total page 968 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acoustic Emission Under Biaxial Stresses in Unflawed 21 6 9 and 304 Stainless Steel written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic emission (AE) testing has been carried out with uniaxial and biaxial (2:1 stress ratio) stressing of smooth samples of 21-6-9 and 304 stainless steel (SS). Uniaxial testing was done with simple tensile and compression samples as well as with the special biaxial specimens. Biaxial tensile stressing was accomplished with a specially designed specimen, which had been used previously to characterize AE in 7075 aluminum under biaxial stressing. Results were obtained for air-melt and for vacuum-melt samples of 21-6-9 SS. The air-melt samples contain considerably more inclusion particles than the vacuum-melt samples. For the 304 SS, as received material was examined. To allow AE correlations with microstructure, extensive characterization of the 21-6-9 microstructure was carried out. Significant differences in AE occur in biaxially stressed specimens as compared to uniaxially stressed samples. 15 figures, 3 tables.
Download or read book Acoustic Emission Under Applied Stress written by B. H. Schofield and published by . This book was released on 1963 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report concerns specific investigation undertaken to assess the role of the surface oxide layer in the generation of acoustic pulses in metals, i.e., acoustic emission. Experiments were conducted on single crystals of aluminum of different crystallographic orientation. The specimens were pulled in tension both in atmosphere and exposed to etchant solutions. Results demonstrated the oxide layer is not itself an emission source and that the emission characteristics are significantly modified as a result of the influence of the oxide on the deformation behavior of the specimens. Specific observations suggest the operative mechanism of emission generation and the importance of the role played by the surface condition in the deformation of metals.
Download or read book Acoustic Emission Amplitude Distribution Analysis for 7075 Aluminum During Tensile Loading written by A. L. Phillips and published by . This book was released on 1983 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Correlation Between Acoustic Emission and Microstructure Final Technical Report written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic emission from pure metals undergoing deformation is caused by dislocation unpinning and can be described by a theory which was a modified version of Gilman's mobile dislocation density theory. Acoustic emission from alloys can be dislocation related, but is primarily due to inclusion fracture. Factors affecting this include inclusion size, inclusion density, and the stress state. Inclusions crack more frequently during tensile testing than during fracture toughness testing.
Download or read book Influence of the Matrix on Acoustic Emission Due to Inclusion Fracture in 7075 T6 Aluminum Alloy written by Jane Wishart Maclachlan and published by . This book was released on 1983 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Austenitic Steels at Low Temperatures written by T. Horiuchi and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for alternate energy sources has led to the develop ment of prototype fusion and MHD reactors. Both possible energy systems in current designs usually require the use of magnetic fields for plasma confinement and concentration. For the creation and maintenance of large 5 to 15 tesla magnetic fields, supercon ducting magnets appear more economical. But the high magnetic fields create large forces, and the complexities of the conceptual reactors create severe space restrictions. The combination of re quirements, plus the desire to keep construction costs at a mini mum, has created a need for stronger structural alloys for service at liquid helium temperature (4 K). The complexity of the required structures requires that these alloys be weldable. Furthermore, since the plasma is influenced by magnetic fields and since magnet ic forces from the use of ferromagnetic materials in many configur ations may be additive, the best structural alloy for most applica tions should be nonmagnetic. These requirements have led to consideration of higher strength austenitic steels. Strength increases at low temperatures are achieved by the addition of nitrogen. The stability of the austenitic structure is retained by adding manganese instead of nickel, which is more expensive. Research to develop these higher strength austenitic steels is in process, primarily in Japan and the United States.
