Download or read book Study of Grain Refinement in Al Alloy 2519 Using Backscattering Orientation Contrast Mode in the Scanning Electron Microscope written by and published by . This book was released on 1992 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of variations in thermomechanical processing (TMP) parameters on grain refinement in 2519 A1-Cu alloy were studied. Refined grains enhance tensile ductility and are a prerequisite for superplastic response. The TMP variables were adjusted based on panicle stimulated nucleation (PSN) theory. Process modifications included increased initial overaging time and decreased subsequent warm rolling temperatures. Backscatter orientation-contrast (BSOC) techniques for the scanning electron microscope (SEM) were developed to achieve grain-orientation contrast An accelerating voltage of 5KV resulted in increased intensities for atomic number and orientation contrast. Both grains and theta- phase (A12Cu) precipitates were revealed on the same micrograph at higher resolutions than attainable in the optical microscope. Quantitative data from micrographs were obtained using image analysis methods. A method based on statistical considerations was developed to determine an approximate critical theta-phase particle diameter (d sub crit) for PSN. The theta-phase particle distribution was shown to be an important factor for grain refinement via PSN.
Download or read book Study of Grain Refinement in Al Alloy 2519 Using Backscatter Orientation contrast Mode in the Scanning Electron Microscope written by Jeffrey Robert Dunlap and published by . This book was released on 1992 with total page 51 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 1993 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of Precipitation and Recrystallization in A1 Alloy 2519 by Backscattered Electron Imaging Methods written by Peter Joseph Zohorsky and published by . This book was released on 1993 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study examines the effects of pre-strain deformation temperature, overaging temperature, and other variations in thermomechanical processing (TMP) on the mean size and size distribution of q-phase precipitate particles in Al alloy 2519. Examination was performed using the scanning electron microscope in the backscattered imaging mode and quantitative image analysis methods were employed. The goal was to find a combination of TMP parameters which produces q-phase particles exceeding a critical diameter for particle stimulated nucleation (PSN) of recrystallization. A necessary prerequisite for superplasticity is a uniformly fine, equiaxed grain size and PSN is theorized to be capable of such grain refinement. Such a microstructure has been developed in Aluminum alloys containing large second phase particles when the alloys are subjected to cold work and recrystallization treatments.
Download or read book Study of Precipitation and Recrystallization in A1 Alloy 2519 by Backscattered Electron Imaging Methods written by Peter Joseph Zohorsky and published by . This book was released on 1993 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study examines the effects of pre-strain deformation temperature, overaging temperature, and other variations in thermomechanical processing (TMP) on the mean size and size distribution of q-phase precipitate particles in Al alloy 2519. Examination was performed using the scanning electron microscope in the backscattered imaging mode and quantitative image analysis methods were employed. The goal was to find a combination of TMP parameters which produces q-phase particles exceeding a critical diameter for particle stimulated nucleation (PSN) of recrystallization. A necessary prerequisite for superplasticity is a uniformly fine, equiaxed grain size and PSN is theorized to be capable of such grain refinement. Such a microstructure has been developed in Aluminum alloys containing large second phase particles when the alloys are subjected to cold work and recrystallization treatments.
Download or read book Masters Theses in the Pure and Applied Sciences written by Sade H Shafer and published by Springer Science & Business Media. This book was released on 1995 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cited in Sheehy, Chen, and Hurt . Volume 38 (thesis year 1993) reports a total of 13,787 thesis titles from 22 Canadian and 164 US universities. As in previous volumes, thesis titles are arranged by discipline and by university within each discipline. Any accredited university or college with a grad
Download or read book Assessment of Grain Refinement by Microtexture Analysis in Thermomechanically Processed Al 2519 Alloy written by Steven L. Stancy and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first part of this study involved determining the mechanism by which elevated-temperature deformation occurred for selected tensile specimens from previous research on thermomechanically processed Al2519 alloy. Microtexture information in the form of discrete pole figures indicated that the most highly superplastic material had completely recrystallized and deformed via grain boundary sliding, whereas material that did not display superplastic behavior deformed via slip. The second part of the study was designed to achieve further refinement of the microstructure of Al2519 using the particle stimulated nucleation (PSN) model as a guide. Using the overaging parameters of the thermomechanical process (TMP) that had yielded the greatest elongation in previous work, additional material was processed but with varying final total processing strain. The resulting material was analyzed using backscatter electron (BSE) microscopy methods to evaluate the effect of total processing strain on the average grain size. The smallest true volume grain size was associated with the material with the highest total processing strain. jg p3.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1993 with total page 1690 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessment of Grain Refinement by Microtexture Analysis in Thermomechanically Processed Al 2519 Alloy written by Steven L. Stancy and published by . This book was released on 1995 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first part of this study involved determining the mechanism by which elevated-temperature deformation occurred for selected tensile specimens from previous research on thermomechanically processed Al2519 alloy. Microtexture information in the form of discrete pole figures indicated that the most highly superplastic material had completely recrystallized and deformed via grain boundary sliding, whereas material that did not display superplastic behavior deformed via slip. The second part of the study was designed to achieve further refinement of the microstructure of Al2519 using the particle stimulated nucleation (PSN) model as a guide. Using the overaging parameters of the thermomechanical process (TMP) that had yielded the greatest elongation in previous work, additional material was processed but with varying final total processing strain. The resulting material was analyzed using backscatter electron (BSE) microscopy methods to evaluate the effect of total processing strain on the average grain size. The smallest true volume grain size was associated with the material with the highest total processing strain. jg p3.
Download or read book Government Reports Annual Index written by and published by . This book was released on 1993 with total page 1832 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermomechanical Processing of Aluminum Alloy 2519 for Grain Refinement and Superplasticity written by Scott D. Bohman and published by . This book was released on 1992 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transmission Electron Microscopy written by David B. Williams and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron microscopy has revolutionized our understanding the extraordinary intellectual demands required of the mi of materials by completing the processing-structure-prop croscopist in order to do the job properly: crystallography, erties links down to atomistic levels. It now is even possible diffraction, image contrast, inelastic scattering events, and to tailor the microstructure (and meso structure ) of materials spectroscopy. Remember, these used to be fields in them to achieve specific sets of properties; the extraordinary abili selves. Today, one has to understand the fundamentals ties of modem transmission electron microscopy-TEM of all of these areas before one can hope to tackle signifi instruments to provide almost all of the structural, phase, cant problems in materials science. TEM is a technique of and crystallographic data allow us to accomplish this feat. characterizing materials down to the atomic limits. It must Therefore, it is obvious that any curriculum in modem mate be used with care and attention, in many cases involving rials education must include suitable courses in electron mi teams of experts from different venues. The fundamentals croscopy. It is also essential that suitable texts be available are, of course, based in physics, so aspiring materials sci for the preparation of the students and researchers who must entists would be well advised to have prior exposure to, for carry out electron microscopy properly and quantitatively.
Download or read book An Analysis of the Grain Refinement of Magnesium by Zirconium written by Partha Saha and published by . This book was released on 2010 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Design of Experiments (DOE) approach was used to conduct a systematic study of the grain refinement of magnesium by zirconium; variables included the amount of zirconium, the pouring temperature, and the settling time prior to casting. Samples were poured into a special "hockey puck" mold designed to reproduce the conditions in permanent mold casting. Optical and scanning electron microscopy (SEM) was utilized to measure the grain size in the final microstructure. Sample dissolution followed by SEM was used to characterize zirconium particle size and morphology both in the master alloy and grain refined samples, while an AccuSizer 770 Photozone/Light Obscuration instrument was used to measure total particle size distributions in the master alloy and grain refined samples. Transmission Electron Microscopy (TEM) was used to identify particles that likely act as suitable heterogeneous nucleation sites for grain refinement. The TEM results show that a range of particle sizes are likely substrates and that only zirconium particles which are faceted are likely nucleation sites. It is apparent that only 1 to 3% of the total particles serve as nucleation sites, but a comparison of the grain density vs. faceted particle density shows close agreement. Equal Channel Angular Extrusion (ECAE) processing of the magnesium-15wt% zirconium master alloy to increase the number of faceted particles resulted in improved grain refinement efficacy. This work suggests that there is a tremendous potential to engineer a more efficient grain refiner.
Download or read book The Science of Armour Materials written by Ian Crouch and published by Woodhead Publishing. This book was released on 2016-09-21 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Science of Armour Materials comprehensively covers the range of armor materials from steels and light alloys, through glasses and ceramics, to fibers, textiles, and protective apparel. The book also discusses aspects of analytical and numerical modeling, as well as laboratory-based high-strain rate testing and ballistic testing methodologies. Each chapter is written from an international perspective, including reviews of the current global literature, and incorporates case studies that focus upon real life applications, research outcomes, and lessons learned. The threat spectrum is restricted to small arms ammunition, high velocity fragments, and stab and spike attacks, as well as blast loadings. - Features input from an editor who is an expert in his field: Dr. Ian Crouch, the author of over 80 publications in his field, with three patents to his name - Provides systematic and comprehensive coverage of armor materials, modeling, and testing - Offers a cross-disciplinary approach that brings together expertise in materials science and defense engineering - Discusses aspects of analytical and numerical modeling, as well as laboratory-based high-strain rate testing and ballistic testing methodologies
Download or read book Characterization of Minerals Metals and Materials 2020 written by Jian Li and published by Springer Nature. This book was released on 2020-01-23 with total page 723 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection gives broad and up-to-date results in the research and development of materials characterization and processing. Topics covered include advanced characterization methods, minerals, mechanical properties, coatings, polymers and composites, corrosion, welding, magnetic materials, and electronic materials. The book explores scientific processes to characterize materials using modern technologies, and focuses on the interrelationships and interdependence among processing, structure, properties, and performance of materials.
Download or read book High Interstitial Stainless Austenitic Steels written by Hans Berns and published by Springer Science & Business Media. This book was released on 2012-11-08 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: High Interstitial Stainless Austenitic Steels is of interest to all engineers and resaerchers working with stainless steel, either at universities or R&D departments in Industry. The new applications described appeal to design engineers while procees engineers find interesting challenges. These novel steels enter more and more industrial applications. Their development is presented by this book in its entirety, starting from the electronic scale of components. This makes it particlularly attractive to Materials Scientists and Metal Physicists.
Download or read book Welding Metallurgy written by Sindo Kou and published by John Wiley & Sons. This book was released on 2003-03-31 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: Updated to include new technological advancements in welding Uses illustrations and diagrams to explain metallurgical phenomena Features exercises and examples An Instructor's Manual presenting detailed solutions to all the problems in the book is available from the Wiley editorial department.
