An Introduction to Metallic Glasses and Amorphous Metals

Description

An Introduction to Metallic Glasses and Amorphous Metals gives a background on the physics of materials, describing relevant experimental techniques. The book presents the necessary background in physics, thermodynamics, and the mechanics of solids, before moving on to cover elasticity, plasticity, fracture and the anelastic behavior of metallic glasses, relating these properties to chemical composition, atomic arrangement, microstructure, and methods of preparation. In addition, it compares the structure-property relationships specific to metallic glasses with polycrystalline metals and alloys and describes the properties and characteristics of metallic glasses. The general features and behavior of metallic glasses are also analyzed and summarized. The book includes full derivations of theory and equations and presents a compendium of experimental methods used in materials science to characterize and study metallic glasses and amorphous solids. The title is a comprehensive resource for any researcher interested in the materials science of metallic glasses and amorphous materials. Front_cover Front-Matter Copyright_2021 Contents 1 Introduction References 2 Making of metallic glasses and applications 2.1 Applications of metallic glasses Aerospace and beyond Protective shield Application as compliant mechanisms Application as gears Application as mirrors Application to corrosion resistance Application to solar wind collection Application as magnetic sensors Application as super-conducting sensor Biological applications of metallic glasses Recent developments of metallic glasses as biomaterials Mg60Zn35Ca5 alloy Ti40Cu36Pd14Zr10 alloy Non-degradable metallic glasses (Ti-, Zr-, Fe-, Pt-based MGs) Zr-based metallic glasses Fe-based metallic glasses Pt-based metallic glasses Mg-, Zn-, Ca-, Sr-based metallic glasses Metallic glass transformers Sporting equipment and personal items Optical, magnetic, and electrical Amorphous silicon solar cells Jewellery Metallic plasticine Rewritable DVDs Manufacturing process How the material functions in a system? References 2.2 Making metallic glasses Casting into a mold Spinning wheel method High-pressure torsion Ti–Ni alloy Fe78B8.5Si9P4.5 alloy ZrTiNiCu alloy Ball milling Cold rolling References 3 Solidification 3.1 Solidification by crystallization Liquid –> solid transformation by crystallization Nucleation Nucleation phenomenon and physical process Nucleation kinetics Embryos, nuclei, and critical size Temperature dependence of nucleation Structural dependence of nucleation Crystal growth Viscosity Kinetics of crystallization Assumptions for isothermal crystallization Homogeneous nucleation and spherical growth Instantaneous heterogeneous nucleation and spherical growth Random nucleation and surface growth Random nucleation and diffusion controlled spherical growth Microstructure of solidified metals Stereology of micro-structures Analysis of the KJMA equation Temperature dependence of the crystallization rate References 3.2 Solidification of glass The process Use of the terms ``amorphous'' and ``glass'' Variety of glasses Three characteristics common to all glasses Diffuse halo X-ray scattering pattern Step at Tg on DSC curve Gradient change at Tg in dilatometry Relationship between cooling rate and vitrification TTT diagram for aluminium Continuous cooling transformation (CCT) diagrams Brief history of metallic glasses Glass-forming ability Reduced glass transition temperature Fragility The cage effect References 4 Characterization of metallic glasses 4.1 Glass transition theories Introduction Kinetic theory (WLF) Free volume theory Entropy theory Stress fluctuations' theory Viscoelastic theory Mode coupling theory (MCT) Geometrical frustration theory Cluster jamming theory Space-time bubbles' theory Local transition events Conclusions References 4.2 Mechanical testing Tensile testing Measuring the sample Calculating elastic properties Compression testing Shear testing Hydrostatic testing Surface hardness testing The science and engineering of hardness testing Testing at high temperature Dynamic mechanical testing References 5 Models of structure Atomic arrangements in solids Atoms and their properties Models of atomic packing in crystals Models of atomic packing in metallic glasses Ideal amorphous solid structure Structure based on randomly oriented clusters Models of micro-structure in metals Poly-crystalline metals Heterogeneity of structure in poly-crystalline metals Heterogeneity of structure in metallic glasses References 6 Magnetic properties of amorphous metallic alloys Section 1. The history of magnetism Ancient period (from the 1st to 18th century) Electromagnetic age (the 19th century) Development of magnetism (the 20th century) Age of applications (from the 20th to 21st century) Atomic-scale magnetism Magnetism of one electron Angular momentum Orbital moment Spin moment The total magnetic moment of one electron Magnetism of one atom Pauli exclusion principle Magnetic moment of an atom Hund's rules Macroscopic-scale magnetism Magnetization (M) Magnetic susceptibility Diamagnetism and paramagnetism Ferromagnetism Molecular field theory Hysteresis loop Anisotropy The classification of ferromagnetic materials Hard magnetic materials Soft magnetic materials Section 2. Applications of amorphous alloys Soft magnetic behavior of Fe-based amorphous alloys Fabrication techniques Copper mold casting J-quenching combined with fluxing technique Powder metallurgy Additive manufacturing (or 3D printing) technique Enhancement of soft magnetic properties Applications of commercialized Fe-based BMGs Magnetic behavior of Nd-based amorphous hard magnets Models for the coercivity of Nd-based amorphous alloys Microstructure and compositional characteristics of amorphous phase in the Nd60Fe30Al10 bulk magnet Enhancing the magnetic property by alloying elements Magneto-caloric bulk amorphous alloys Magneto-caloric effect A brief history of the magneto-caloric effect Characterization of magneto-caloric materials Magneto-caloric bulk metallic glasses Section 3. Outlook of magnetic amorphous alloys References 7 Elasticity of metallic gasses Continuum mechanics Affine and non-affine deformation Example of macroscopic elastic deformation Strain measured by the Voronoi method (atomic level) Strain measured by the X-ray method: crystalline solids Strain measured by the X-ray method: amorphous solids Deformation in bulk metallic glass Elastic modulus by the X-ray method Deformation in Zr55Al10Ni5Cu30 metallic glass Contact probability and average spacing Deformation in Zr46.5Cu45Al7Ti1.5 metallic glass Deformation in Zr64Cu16Ni10Al10 metallic glass under cooling Deformation in thin film metallic glass Structural evolution in Zr50Cu50 metallic glass during compression Structural evolution in Zr64.13Cu15.75Ni10.12Al10 during heating Changes in atomic structure revealed by radial distribution References 8 Introduction to anelastic deformation Creep Stress relaxation Mechanical relaxation and dynamic loss modulus Time and temperature dependent behavior Creep of aluminium-based metallic glass Creep of Zr-based metallic glass Dynamic relaxation in Fe63Al27 metallic glass Free-volume anelastic deformation of metallic glasses The β relaxation in La–Ni–Al metallic glass Definitions of shear viscosity 1. Newton's definition 2. Stokes' definition 3. Hagen–Poiseuille's definition References 9 Plastic deformation and yield strength of metals Time–temperature deformation maps T–T deformation map for poly-crystalline metal (silver) T–T deformation map for metallic glass Mechanisms of plasticity at the atomic level Plasticity in metallic glasses Plastic flow in MGs Serrated flow at macroscopic level Environmental temperature effects Dynamical behavior Interaction of elastic strain field and shear bands Non-serrated flow behavior at very low temperatures Microstructure origin of the deformation behavior at very low temperature Micro-structure effects Serrated flow in 5 different alloy systems Serrated flow in a metallic glass containing crystalline phases Serrated flow at microscopic level Serrated flow during nano-indentation Serrated flow in different alloy systems Serrated flow in a monolithic metallic glass modified by ion irradiation Serrated flow during nano-scratching Summary and outlook References 10 Fracture mechanics of metallic glasses Fracture strength of an uncracked material Shear fracture – Coulomb–Mohr theory Tensile fracture – Griffith's fracture criterion Calculation of elastic strain energy Calculation of crack surface energy Solution for fracture stress Fracture toughness Limits of applicability of Eq. (10.24) Irwin fracture criterion Fatigue and fracture of metallic glasses Loads and variation during use Time to crack initiation Crack growth rates Life prediction Dependence of strength on sample size Instability and morphology of fracture References A Thermodynamics of a system Molecular system Enthalpy Entropy Forces between atoms, molecules, and particles Types of physical forces Interatomic forces Lennard-Jones interatomic potential Buckingham potential Morse potential Many-atom potential Stillinger–Weber potential Embedded atom model potential Gibbs free energy Liquid-to-solid phase transformation Computation of cluster potential References Index Back_cover