Download or read book Glass Stability and Kinetic Analysis of Iron metalloid Bulk Metallic Glass written by and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multicomponent Fe-based bulk metallic glasses (BMGs) with a combination of excellent properties such as good soft magnetic properties, high strength, high hardness, and high corrosion resistance have attracted increasing attention both from a basic science research standpoint and due to their industrial application potential. However, many of the elemental additions which lead to the easiest glass formation are expensive. The identification of alloys composed of abundant and inexpensive elements that still retain excellent properties would promote applications for engineering and industry. In short, the development of the Fe-based BMG without any glass-forming metal elements and with high glass forming ability is desired. This study shows that the thermal stability of the Fe-based alloys can be improved beyond a simple rule of mixtures prediction by utilizing a well-balance multi-metalloid approach. The kinetics aspect of glass-forming ability is studied experimentally for Fe-B-Si-P alloys. The systematic variation in alloy composition gives access to differences in phase selection and the final dimensions of glass formation. Two alloys, representing the best glass-forming composition and the poorest glass-forming composition, were studied in terms of their stability to crystallization, solidification microstructure evolution and thermal history. The utility of the wedge-casting technique is developed to examine bulk glass-forming alloys by combining multiple temperature profiles of the quenching melt with a measurement-based kinetic analysis of the phase selection competition and critical cooling rate conditions. Based upon direct thermal measurement, microstructural analysis and kinetic modeling, it was found that both representative alloys show a board spectrum of solidification microstructures which include a critical cooling rate range. The kinetic competition in the formation of certain phases can enhance or detract from the final dimension of bulk glass formation of the representative alloys. Practical strategies in crystallization kinetics analysis and microstructure control are developed to extend the knowledge of phase competition leading to successful synthesis of BMGs. Low cost Fe-metalloid BMGs will provide a great advantage for the transition to commercial applications when material cost is a critical issue.

Download or read book Bulk Metallic Glasses written by C. Suryanarayana and published by CRC Press. This book was released on 2011-06-03 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt: In spite of the large amount of research activity in this subfield of materials science and engineering, there is no single book available that provides background information, methods of synthesis, characterization procedures, properties, and potential and existing applications.of bulk metallic glasses. Written in an easy-to-understand style by pioneering researchers in this field, Bulk Metallic Glasses is one of the first books to coherently discuss the synthesis, processing, properties, and applications of these unique materials. The book explores the differences between nanocrystalline, glassy, and amorphous solids as well as the thermodynamics and kinetics and various processing methods of glass formation. It critically compares the different criteria for glass formation, describes the advantages and limitations of experimental methods for synthesizing bulk metallic glasses in assorted sizes and shapes, and examines the kinetics of crystallization/devitrification and the mechanisms of transformations. It also covers the density, diffusivity, thermal expansion, electrical resistivity, specific heat, viscosity, corrosion resistance, mechanical behavior, and magnetic properties of bulk metallic glasses. After presenting a wide array of applications, the book concludes with a discussion on the future of these materials. The adoption of bulk metallic glasses into existing systems is besieged by many obstacles but due to their interesting combination of properties, future applications may be unlimited. A one-stop resource on all aspects of bulk metallic glasses, this book demonstrates the immense potential of these novel materials. It clearly elucidates the background, detailed methods of synthesis and characterization, structure, and properties of bulk metallic glasses.

Download or read book Bulk Metallic Glasses and Their Composites written by Hesham Ezzat Khalifa and published by . This book was released on 2009 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: A design protocol utilizing common elements for bulk metallic glass formation has been employed to develop novel, low cost Fe-, and Ti- based bulk metallic glasses. A critical obstacle that was successfully overcome in this work is the omission of beryllium in these alloys. Beryllium is of vital importance in many bulk metallic glass forming systems, but it is expensive and poses considerable health risks. Bulk metallic glasses in these novel Fe-, and Ti-based systems exhibit extremely high mechanical strength and excellent thermal stability. Devitrification and cooling rate experiments were used to identify crystalline phase formation and assess activation energy for crystallization, as well as to explore and develop ductile BMG composites. To better control microstructure in these BMG composites, a novel processing technique, called semi-solid forging was developed, wherein the alloy melt is heated to above the melt temperature of the glass, but below the melt temperature of the ductile crystalline phase. Such an approach permits the maintenance of a glassy, or nanocrystalline matrix phase, while simultaneously coarsening and homogenizing the ductile, secondary phase. This processing approach leads to enhanced ductility in the alloys, which, to this point, has not been observed using conventional casting methods. The combination of novel, low-cost, alloy compositions with semi-solid forging has been successfully utilized to develop new high strength structural materials with enhanced ductility and toughness. Microstrutural and mechanical properties of these novel, toughened, BMG composites are presented. A comprehensive analysis of the relationship between deformation mechanisms and microstructure reveals that enhanced ductility is predicated on matching fundamental mechanical and microstructural length scales in a Ti-Ni-Si-Mo BMG composite. Under optimized microstructural conditions, a maximum compressive strength exceeding 2400 MPa with ~ 30% total strain to failure was achieved. Furthermore, a 400% increase in fracture toughness over the monolithic glass, and tensile ductility of 3.5% were observed. The design of conventional, crystalline, high-performance structural materials is governed by optimizing combinations of mechanical properties such as strength, ductility, toughness, and elasticity. In general though, high strength comes at the expense of ductility. The development of ductile BMG composites represents the dawn of a new era in structural materials that couples ultra high strength with considerable ductility and enhanced fracture toughness.

Download or read book Fe Based Bulk Metallic Glasses written by Mihai Stoica and published by Springer. This book was released on 2017-02-08 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mihai Stoica investigates in details the glass formation of two model alloys, [(Fe0.5Co0.5)0.75B0.2Si0.05]96Nb4 and Fe74Mo4P10C7.5B2.5Si2. More than 20 master alloys using different raw materials were prepared. Besides the typical calorimetry and X-Ray diffraction, magnetic measurements were employed to analyze the amorphicity degree of the sample. Two new bulk metallic glass-forming alloy compositions are designed and possible preparation routes are proposed.

Download or read book Bulk Metallic Glasses written by C. Suryanarayana and published by CRC Press. This book was released on 2010-08-24 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: In spite of the large amount of research activity in this subfield of materials science and engineering, there is no single book available that provides background information, methods of synthesis, characterization procedures, properties, and potential and existing applications.of bulk metallic glasses. Written in an easy-to-understand style by pioneering researchers in this field, Bulk Metallic Glasses is one of the first books to coherently discuss the synthesis, processing, properties, and applications of these unique materials. The book explores the differences between nanocrystalline, glassy, and amorphous solids as well as the thermodynamics and kinetics and various processing methods of glass formation. It critically compares the different criteria for glass formation, describes the advantages and limitations of experimental methods for synthesizing bulk metallic glasses in assorted sizes and shapes, and examines the kinetics of crystallization/devitrification and the mechanisms of transformations. It also covers the density, diffusivity, thermal expansion, electrical resistivity, specific heat, viscosity, corrosion resistance, mechanical behavior, and magnetic properties of bulk metallic glasses. After presenting a wide array of applications, the book concludes with a discussion on the future of these materials. The adoption of bulk metallic glasses into existing systems is besieged by many obstacles but due to their interesting combination of properties, future applications may be unlimited. A one-stop resource on all aspects of bulk metallic glasses, this book demonstrates the immense potential of these novel materials. It clearly elucidates the background, detailed methods of synthesis and characterization, structure, and properties of bulk metallic glasses.

Download or read book Bulk Metallic Glasses written by C. Suryanarayana and published by CRC Press. This book was released on 2017-11-22 with total page 543 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reflecting the fast pace of research in the field, the Second Edition of Bulk Metallic Glasses has been thoroughly updated and remains essential reading on the subject. It incorporates major advances in glass forming ability, corrosion behavior, and mechanical properties. Several of the newly proposed criteria to predict the glass-forming ability of alloys have been discussed. All other areas covered in this book have been updated, with special emphasis on topics where significant advances have occurred. These include processing of hierarchical surface structures and synthesis of nanophase composites using the chemical behavior of bulk metallic glasses and the development of novel bulk metallic glasses with high-strength and high-ductility and superelastic behavior. New topics such as high-entropy bulk metallic glasses, nanoporous alloys, novel nanocrystalline alloys, and soft magnetic glassy alloys with high saturation magnetization have also been discussed. Novel applications, such as metallic glassy screw bolts, surface coatings, hyperthermia glasses, ultra-thin mirrors and pressure sensors, mobile phone casing, and degradable biomedical materials, are described. Authored by the world’s foremost experts on bulk metallic glasses, this new edition endures as an indispensable reference and continues to be a one-stop resource on all aspects of bulk metallic glasses.

Download or read book Metallic Glasses written by Dragica Minić and published by BoD – Books on Demand. This book was released on 2020-02-05 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The term "metallic glasses" is widely used to denote the amorphous alloys obtained by rapid quenching techniques. These materials are characterized by short range atom ordering without translational periodicity of the structure. Kinetic and thermodynamic metastability is one of the main characteristics generally related to metallic glasses, while their thermally induced microstructural transformations could result in deterioration or improvement of the functional properties. Due to their favorable magnetic, electrical, mechanical, and anti-corrosion properties, metallic glasses as new and attractive materials have found application in many areas of modern industries - electronics, construction industry, aerospace industry; as well as chemistry, biomedicine, and surgery.

Download or read book Stability of Bulk Metallic Glass Structure written by D. B. Williams and published by . This book was released on 2003 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamental origins of the stability of the (Pd-Ni){sub 80}P{sub 20} bulk metallic glasses (BMGs), a prototype for a whole class of BMG formers, were explored. While much of the properties of their BMGs have been characterized, their glass-stability have not been explained in terms of the atomic and electronic structure. The local structure around all three constituent atoms was obtained, in a complementary way, using extended X-ray absorption fine structure (EXAFS), to probe the nearest neighbor environment of the metals, and extended energy loss fine structure (EXELFS), to investigate the environment around P. The occupied electronic structure was investigated using X-ray photoelectron spectroscopy (XPS). The (Pd-Ni){sub 80}P{sub 20} BMGs receive their stability from cumulative, and interrelated, effects of both atomic and electronic origin. The stability of the (Pd-Ni){sub 80}P{sub 20} BMGs can be explained in terms of the stability of Pd{sub 60}Ni{sub 20}P{sub 20} and Pd{sub 30}Ni{sub 50}P{sub 20}, glasses at the end of BMG formation. The atomic structure in these alloys is very similar to those of the binary phosphide crystals near x=0 and x=80, which are trigonal prisms of Pd or Ni atoms surrounding P atoms. Such structures are known to exist in dense, randomly-packed systems. The structure of the best glass former in this series, Pd{sub 40}Ni{sub 40}P{sub 20} is further described by a weighted average of those of Pd{sub 30}Ni{sub 50}P{sub 20} and Pd{sub 60}Ni{sub 20}P{sub 20}. Bonding states present only in the ternary alloys were found and point to a further stabilization of the system through a negative heat of mixing between Pd and Ni atoms. The Nagel and Tauc criterion, correlating a decrease in the density of states at the Fermi level with an increase in the glass stability, was consistent with greater stability of the Pd{sub x}Ni{sub (80-x)}P{sub 20} glasses with respect to the binary alloys of P.A valence electron concentration of 1.8 e/a, which ensures the superpositioning of the first peak in the structure factor with twice the Fermi momentum, was used to calculate the interatomic potential of these alloys. The importance of Pd to the stability of the alloys is evidenced by the fact that replacing Ni with Pd places the nearest neighbor distances at more attractive positions in this potential.

Download or read book Christ Church Shelburne Nova Scotia written by and published by . This book was released on 1940* with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rapidly Quenched Metals written by S Steeb and published by Elsevier. This book was released on 2012-12-02 with total page 1163 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapidly Quenched Metals, Volume I covers the proceedings of the Fifth International Conference on Rapidly Quenched Metals, held in Wurzburg, Germany on September 3-7, 1984. The book focuses on amorphous and crystalline metals formed by rapid quenching from the melt. The selection first covers the scope and trends of developments in rapid solidification technology, rapid solidification, and undercooling of liquid metals by rapid quenching. Discussions focus on experimental method, powders, strip, particulate production, consolidation, and alloys and alloy systems. The text then examines the solidification of undercooled liquid alloys entrapped in solid; crystallization kinetics in undercooled droplets; and grain refinement in bulk undercooled alloys. The manuscript tackles the undercooling of niobium-germanium alloys in a 100 meter drop tube; influence of process parameters on the cooling rate of the meltspinning process; and the mechanism of ribbon formation in melt-spun copper and copper-zirconium. The formation and structure of thick sections of rapidly-solidified material by incremental deposition and production of ultrafine dispersions of rare earth oxides in Ti alloys using rapid solidification are also mentioned. The selection is a valuable reference for physicists, chemists, physical metallurgists, and engineers.

Download or read book Metals Abstracts written by and published by . This book was released on 1998 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thermodynamics Kinetics and Crystallization of Pt57 3Cu14 6Ni5 3P22 8 Bulk Metallic Glass Forming Alloy written by Benjamin A. Legg and published by . This book was released on 2006 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study utilizes differential scanning calorimetry (DSC) to characterize the thermodynamics, kinetics and crystallization b processes of a new Pt57.3Cu14.6Ni5.3P22.8 bulk metallic glass forming alloy. The heat capacity of the alloy is measured for the crystalline, glassy, and supercooled liquid phases. This data is used to obtain thermodynamic driving forces for crystallization and quantify the thermodynamic fragility. Kinetic properties of the alloy are investigated by observing the glass transition under different heating rates. The heating rate dependence of the glass transition is then used to calculate the kinetic fragility and estimate how the material's viscosity varies with temperature. DSC is also used to observe the crystallization event at variety of temperatures and generate a Time-Temperature-Transformation (TTT) diagram for crystallization. The crystallization results and TTT diagram are compared with thermodynamic and kinetic data using classical nucleation theory, and different models for crystallization are discussed.

Download or read book Introduction to Glass Science and Technology written by James E Shelby and published by Royal Society of Chemistry. This book was released on 2015-11-06 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a concise and inexpensive introduction for an undergraduate course in glass science and technology. The level of the book has deliberately been maintained at the introductory level to avoid confusion of the student by inclusion of more advanced material, and is unique in that its text is limited to the amount suitable for a one term course for students in materials science, ceramics or inorganic chemistry. The contents cover the fundamental topics of importance in glass science and technology, including glass formation, crystallization, phase separation and structure of glasses. Additional chapters discuss the most important properties of glasses, including discussion of physical, optical, electrical, chemical and mechanical properties. A final chapter provides an introduction to a number of methods used to form technical glasses, including glass sheet, bottles, insulation fibre, optical fibres and other common commercial products. In addition, the book contains discussion of the effects of phase separation and crystallization on the properties of glasses, which is neglected in other texts. Although intended primarily as a textbook, Introduction to Glass Science and Technology will also be invaluable to the engineer or scientist who desires more knowledge regarding the formation, properties and production of glass.

Download or read book High Entropy Materials written by Yong Zhang and published by Springer. This book was released on 2019-05-27 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book draws on the latest research to discuss the history and development of high-entropy alloys and ceramics in bulk, film, and fiber form. High-entropy materials have recently been developed using the entropy of mixing and entropy of configuration of materials, and have proven to exhibit unique properties superior to those of conventional materials. The field of high-entropy alloys was born in 2004, and has since been developed for both scientific and engineering applications. Although there is extensive literature, this field is rapidly transforming. This book highlights the cutting edge of high-entropy materials, including their fundamentals and applications. Above all, it reflects two major milestones in their development: the equi-atomic ratio single-phase high-entropy alloys; and the non-equi-atomic ratio dual-phase high-entropy alloys.

Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spark Plasma Sintering of Materials written by Pasquale Cavaliere and published by Springer. This book was released on 2019-02-18 with total page 781 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes spark plasma sintering (SPS) in depth. It addresses fundamentals and material-specific considerations, techniques, and applications across a broad spectrum of materials. The book highlights methods used to consolidate metallic or ceramic particles in very short times. It highlights the production of complex alloys and metal matrix composites with enhanced mechanical and wear properties. Emphasis is placed on the speed of the sintering processes, uniformity in product microstructure and properties, reduced grain growth, the compaction and sintering of materials in one processing step, various materials processing, and high energy efficiency. Current and potential applications in space science and aeronautics, automation, mechanical engineering, and biomedicine are addressed throughout the book.

Download or read book Amorphous Metallic Alloys written by F. E. Luborsky and published by Butterworth-Heinemann. This book was released on 1983 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt: Index of amorphous alloys