Download or read book Synthesis and Deformation of Nanocrystalline Nickel written by Zunayed Ahmed and published by . This book was released on 2001 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deformation of Nanocrystalline Materials at Ultrahigh Strain Rates Microstructure Perspective in Nanocrystalline Nickel written by R. Smith and published by . This book was released on 2006 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocrystalline materials with grain sizes smaller than 100 nm have attracted extensive research in the past decade. Due to their high strength, these materials are good candidates for high pressure shock loading experiments. In this paper, we investigated the microstructural evolutions of nanocrystalline nickel with grain sizes of 10-50 nm, shock-loaded in a range of pressures (20-70 GPa). A laser-driven isentropic compression process was applied to achieve high shock-pressures in a timescale of nanoseconds and thus the high-strain-rate deformation of nanocrystalline nickel. Postmortem transmission electron microscopy (TEM) examinations reveal that the nanocrystalline structures survive the shock deformation and that dislocation activity is the prevalent deformation mechanism when the grain sizes are larger than 30 nm, without any twinning activity at twice the stress threshold for twin formation in micrometer-sized polycrystals. However, deformation twinning becomes an important deformation mode for 10-20 nm grain-sized samples.
Download or read book The Systematic Study of Deformation and Fracture Mechanism of Nano Crystalline Nickel written by Manish Sharma and published by . This book was released on 2020-04-14 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present study is initiated with the specific objective of observing, both during and after deformation in Nickel Crystal by TEM experiments, the mechanisms of the deformation and fracture using state of the art experimental tools in high purity, fully dense nanocrystalline metals with a narrow range of gain sizes. The goal is to develop a strategy to reach the rational design of nanomaterials i.e. nanocrystal Nickel with modelled and controlled particles size, morphology, orientation, and crystal structure, i.e. purpose-built nanomaterials, to probe, tune, and optimize their physical, chemical properties and mechanical properties. In our view, to achieve such ambitious challenge, the most pertinent parameter to monitor is the dislocation mechanism of the system. In an attempt to take part in the fascinating nanoworld, and to contribute to its ambitious challenges, the present review will expose the outcome of a novel general concept of nucleation, growth, thin film processing method. Now a days, new concepts of nanocomposites and nano glasses are also being investigated with special emphasis on ceramic composites to increase their strength and toughness. There appears to be a great potential for applications in the near future for nanocrystalline materials. The extensive investigations in recent years on structure-property correlations in nanocrystalline materials have begun to unravel the complexities of these materials, and pave the way for successful exploitation of alloy design principles to synthesize better materials than hitherto available. For the first time, direct and compelling conclusive evidence of the deformation mechanism crossover is provided. In addition, unexpected dislocation activities are also observed in grains as small as 5 nm. Nano beam diffraction observations revealed that a nanocrystalline grain with a size of about 20 nm may experience ultrahigh elastic strain during deformation and the implication of this finding is discussed in detail. Also Understanding the formation mechanisms and role of grain agglomerates in nanocrystalline metals is expected to directly impact the processing methods required to create nanocrystalline metals with improved strength and ductility.
Download or read book Nanocrystalline Nickel Via Pulsed Electrodeposition written by Rachmad Imbang Tritjahjono and published by . This book was released on 2008 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deformation Mechanisms of Nanocrystalline Nickel Studied by In situ X ray Diffraction written by Stefan Brandstetter and published by . This book was released on 2009 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermal Stability and Deformation of Nanocrystalline Nickel written by James Edward Darnbrough and published by . This book was released on 2014 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermal Stability and Deformation of Nanocrystalline Nickel written by James Edward Darnbrough and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Revealing Deformation Spectra of Nanocrystalline Nickel at Elevated Temperatures written by and published by . This book was released on 2011 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Properties of Advanced Materials written by C.J. McHargue and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synthesis and Properties of Advanced Materials provides an overview of some of the most exciting developments in advanced materials. The book contains review papers based on tutorial lectures given at The First Pan American Advanced Study Institute held in Merida, Mexico, 1995. Each paper serves as a comprehensive introduction and review to the topic covered. Topics included: diamond and related materials, nanocrystalline metals and ceramics, Co-based alloys for biomedical applications, high-temperature superconductivity materials, composite materials, cement-based materials, ion-implanted ceramics and structural ceramics. Each chapter emphasizes the relationships among processing parameters, micro-structure and properties. Synthesis and Properties of Advanced Materials provides an excellent review of the state of the art in advanced materials for the working engineer or researcher. Students will also find this text an accessible introduction to the field.
Download or read book Nanomaterials by Severe Plastic Deformation written by Michael J. Zehetbauer and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings of the "Second International Conference on Nanomaterials by Severe Plastic Deformation" review the enormous scientific avalanche that has been developing in the field over recent years. A valuable resource for any scientist and engineer working in this emerging field of nanotechnology.
Download or read book Study of Deformation Behavior of Nanocrystalline Nickel Using Nanoindentation Techniques written by Changli Wang and published by . This book was released on 2010 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocrystalline materials with grain size less than 100 nm have been receiving much attention because of their unparallel properties compared with their microcrystalline counterparts. Because of its high hardness, nanocrystalline nickel has been used for MEMS. Long term thermomechnical properties and deformation mechanism at both ambient and elevated temperatures need to be evaluated which is vital for reliability of its applications as structural material. In this thesis, nanoindentation creep of nanocrystalline nickel with an as-deposited grain size of 14 nm was characterized at elevated temperatures. The nanoindentation creep rate was observed to scale with temperature and applied load (or stress), and could be expressed by an empirical power-law equation for describing conventional crystalline solids. Creep activation energy was found to be close to that for grain boundary self-diffusion in nickel. The activation volume was also evaluated using a stress relaxation technique. The creep results were compared with those for fine-grained nickel in the literature. Possible mechanisms were discussed in light of the creep rate and temperature ranges. To provide a direct comparison, uniaxial creep tests were conducted on nanocrystalline nickel with an as-deposited grain size of 14 nm at 398 K. It was found that stress exponents under the two test conditions are almost the same, indicating a similar creep mechanism. However, the strain rate measured by nanoindentation creep was about 100 times faster than that by uniaxial creep. The rate difference was discussed in terms of stress states and the appropriate selection of Tabor factor. To further explore the time-dependent plastic behavior, multiple unload-reload tests were conducted on electrodeposited nanocrystalline nickel in both compression and tension. A hysteresis was observed during each unload-reload cycle, indicating irreversible energy dissipation. The dissipated energy was evaluated and the energy dissipation rate was found to increase with the flow stress to the third power and sensitive to the stress state (tension or compression). A mechanistic model based on grain boundary sliding was proposed to describe the unload-reload behavior. Experimental results were found to be in good agreement with the model predictions, suggesting the observed hysteresis was indeed caused by grain boundary sliding.
Download or read book Investigation of Deformation Mechanisms in Nanocrystalline Metals and Alloys by in Situ Synchrotron X ray Diffraction written by Jochen Andreas Lohmiller and published by KIT Scientific Publishing. This book was released on 2014-05-22 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, different nanocrystalline metals and alloys were investigated by a synchrotron-based in situ XRD mechanical testing technique in order to investigate the dominant deformation mechanisms. All tested samples show a succession and coexistence of several mechanisms, regardless of grain size, loading condition, or sample geometry. However, the relative shares of the individual mechanisms strongly vary and depend on parameters such as grain size, sample purity, and alloy composition.
Download or read book Cold Rolling Texture of Electrodeposited Nanocrystalline FCC Metals written by Yanling Yang and published by American Academic Press. This book was released on 2018-01-16 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Properties of nanocrystalline metals or alloys cannot be predicted according to the phenomena observed in traditional coarse-grained materials. Nanocrystalline materials exhibit special physical and chemical properties, such as extremely high mechanical strength, outstanding thermal, optical, magnetic and electrical properties. Deformation mechanisms of nanocrystalline materials have been discussed for many years. Previous literatures mainly focus on the investigation of deformation behaviors through in-situ experimental methods such as in-situ TEM observation or simulation methods by modeling. With regard to the in-situ TEM observation, it still remains controversial whether the TEM results can represent the deformation behaviors of bulk nanocrystalline materials. In line with the molecular dynamics simulation method, the materials are frequently assumed to be ideal and the strain rate utilized is extraordinarily high. All the above conditions almost cannot be met or validated through experiments. In this work, it is attempted to explore deformation mechanisms of nanocrystalline face-centered cubic metals or alloys based on texture evolution during plastic deformation. Dislocation movements in plastic deformation process are always followed by formation of deformation texture in most cases, and plastic deformation coordinated by grain boundary sliding and/or grain rotation mechanisms does not incur the occurrence of crystallographic texture. Therefore, investigations on texture evolution during plastic deformation are able to provide powerful evidence for the deformation mechanisms of nanocrystalline materials.
Download or read book Nanocrystalline Materials written by Sie-Chin Tjong and published by Elsevier. This book was released on 2006-06-23 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocrystalline materials with new functionalities show great promise for use in industrial applications - such as reinforcing fillers in novel polymer composites – and substantial progress has been made in the past decade in their synthesis and processing. However, there are several issues that need to be addressed to develop these materials further. Among these, exploration of novel methods for the large-scale synthesis of low cost self-assembled nanostructures is a challenging research topic. Accordingly, there has emerged a demand to study their synthesis-structure-property relationships in order to understand the fundamental concepts underlying the observed physical and mechanical properties.With contributions from leading experts, this book describes the fundamental theories and concepts that illustrate the complexity of the problem in developing novel nanocrystalline materials. It reviews the most up-to-date progress in the synthesis, microstructural characterization, physical and mechanical behavior, and application of nanomaterials.* Investigates the synthesis, characterisation and properties of a huge variety of nanocrystalline materials, and their applications in industry * Keeps the prominent challenges in nanomaterials fabrication at the forefront while offering the most up-to-date scientific findings
Download or read book Structure and Mechanical Properties of Nanophase Materials Theory and Computer Simulations Vs Experiment Volume 634 written by Diana Farkas and published by . This book was released on 2001-07-11 with total page 338 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 Nanostructured Coatings written by Albano Cavaleiro and published by Springer Science & Business Media. This book was released on 2007-02-19 with total page 671 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book delivers practical insight into a broad range of fields related to hard coatings, from their deposition and characterization up to the hardening and deformation mechanisms allowing the interpretation of results. The text examines relationships between structure/microstructure and mechanical properties from fundamental concepts, through types of coatings, to characterization techniques. The authors explore the search for coatings that can satisfy the criteria for successful implementation in real mechanical applications.
Download or read book Microstructure and Mechanical Properties of Nanocrystalline Ni Produced by Three Different Synthesis Techniques written by Florian Dalla Torre and published by . This book was released on 2003 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt:
