Generalized Maxwell model 1970-01-01
The Generalized Maxwell model is a mathematical framework used to describe the viscoelastic behavior of materials. It extends the classical Maxwell model, which represents a viscoelastic substance as a combination of a purely elastic spring and a purely viscous dashpot arranged in series. In the classical Maxwell model, the relationship between stress and strain rate is described by a simple first-order differential equation.
Geometallurgy 1970-01-01
Geometallurgy is an interdisciplinary approach that combines geology, metallurgy, and mining engineering to improve the efficiency and effectiveness of the mining and processing of mineral resources. The primary goal of geometallurgy is to understand the spatial variability of ore characteristics and how these variations affect the extraction and processing of metals. Key components of geometallurgy include: 1. **Geological Mapping**: Detailed geological surveys and mapping are conducted to identify and characterize ore deposits.
Goodman relation 1970-01-01
The Goodman relation, also known as the Goodman diagram or Goodman fatigue criterion, is a graphical representation used in mechanical engineering and materials science to predict the fatigue life of materials under varying levels of mean and alternating stress. It provides a framework for understanding how different loading conditions affect the fatigue strength of materials.
Gorilla Glass 1970-01-01
Gorilla Glass is a brand of specialized glass developed by Corning Inc. It is engineered to be thin, light, and exceptionally strong, making it ideal for use in various electronic devices, including smartphones, tablets, laptops, and wearables. The glass is designed to be resistant to scratches, drops, and other forms of damage, enhancing the durability of devices that use it. Gorilla Glass is made through a unique chemical-strengthening process that increases its toughness compared to regular glass.
Grain boundary 1970-01-01
Grain boundaries are imperfections or interfaces that occur between different crystallographic orientations of grains within a polycrystalline material. A grain is a single crystal within a larger aggregate, and when many such crystals (or grains) come together, their boundaries form the grain boundaries. Key characteristics and roles of grain boundaries include: 1. **Structure**: Grain boundaries can vary in structure and properties depending on the relative orientations of the adjacent grains.
Grain growth 1970-01-01
Grain growth refers to the increase in size of crystallites (grains) in a polycrystalline material during processes such as heat treatment or annealing. This phenomenon occurs when the temperature of a material is elevated, leading to a reduction in the total surface energy of the material. In a polycrystalline solid, grains are separated by interfaces called grain boundaries.
Green strength 1970-01-01
"Green strength" typically refers to the strength or integrity of a material or substance in its uncured or "green" state, particularly in the context of ceramics, polymers, and composites. This term is most commonly used in manufacturing and material science, particularly when discussing processes such as molding or forming before a material has undergone complete curing or hardening.
HARMST 1970-01-01
HARMST stands for "High-Angle Rapid Motion Small Target," which typically refers to a category of targets or objects that are difficult to detect and track due to their rapid movement and small size. Such targets are often of interest in various fields, including military and aerospace applications, where effective tracking and engagement are crucial for operational success.
Hankinson's equation 1970-01-01
Hankinson's equation is a semi-empirical formula used to estimate the shear strength of soils, particularly in the context of site investigation and geotechnical engineering. The equation takes into account various factors that influence soil behavior, such as confining pressure and soil properties.
Helium atom scattering 1970-01-01
Helium atom scattering (HAS) is an experimental technique used in surface science to study the structure and properties of solid surfaces at the atomic level. It involves directing a beam of helium atoms at a surface and analyzing the scattered helium atoms that result from interactions with the surface. This technique takes advantage of the unique properties of helium, especially in its quantum mechanical behavior and its low mass, which make it a sensitive probe for surface characteristics.
Hertzian cone 1970-01-01
The Hertzian cone is a concept in the field of contact mechanics, particularly relating to the study of how materials interact when they come into contact under stress. It is named after Heinrich Hertz, a physicist who contributed significantly to the understanding of contact phenomena. When two elastic bodies come into contact, such as a ball and a flat surface, the contact generates a stress field that propagates into the materials.
Heterostrain 1970-01-01
Heterostrain refers to a type of strain that is not uniform throughout a material or structure, often resulting from differential expansion or contraction due to various factors such as temperature changes, phase transformations, or the presence of different materials. In materials science and engineering, heterostrain can occur in composites or layered materials where each layer or component may respond differently to external forces or environmental conditions. This phenomenon can lead to complex stress distributions, which can affect the mechanical properties, durability, and performance of materials.
High-frequency impulse-measurement 1970-01-01
High-frequency impulse measurement typically refers to techniques used in various fields, such as electronics, telecommunications, and materials science, to analyze responses of systems to high-frequency signals or short-duration impulses. This kind of measurement is crucial for understanding the dynamic behavior of systems, components, or materials under rapid changes.
High-power impulse magnetron sputtering 1970-01-01
High-Power Impulse Magnetron Sputtering (HiPIMS) is an advanced thin-film deposition technique that enhances the traditional magnetron sputtering process by using high-power pulses instead of continuous power. This technology is utilized to create thin films with enhanced properties, which can be utilized in a variety of applications, including coatings for tools, electronics, optics, and more.
High pressure 1970-01-01
High pressure generally refers to a condition where the atmospheric pressure is greater than the surrounding areas. In meteorology, high pressure systems are associated with clear skies and calm weather because the air descends, preventing clouds from forming. Here are some contexts in which "high pressure" can be discussed: 1. **Meteorology**: High pressure systems lead to fair weather as descending air inhibits cloud formation.
Hume-Rothery rules 1970-01-01
The Hume-Rothery rules are guidelines used to predict the solubility limits of one metal in another, particularly in alloy formation. These rules help in understanding the conditions under which two metals can mix or form solid solutions. The Hume-Rothery rules are based on several criteria, which can be summarized as follows: 1. **Atomic Size Factor**: The atomic radii of the two metals should not differ by more than about 15%.
Hydrogen-bonded organic framework 1970-01-01
Hydrogen-bonded organic frameworks (HOFs) are a class of materials characterized by their unique structure, which is stabilized primarily by hydrogen bonding interactions between organic molecules. Unlike traditional covalent or ionic bonds, hydrogen bonds are relatively weak, but they can collectively provide significant stability and structural integrity to the framework.
Hydrogenography 1970-01-01
Hydrogenography is not a widely recognized term in scientific literature or common usage as of my last update in October 2023. However, it appears to be a blend of the words "hydrogen" and "photography," often associated with techniques or methods involving the visualization or analysis of hydrogen in various contexts, particularly in scientific or industrial settings. If the term has evolved or gained specific meaning after 2023, it could relate to a particular technique or field of study.
Impulse excitation technique 1970-01-01
The Impulse Excitation Technique (IET) is a non-destructive testing method used to characterize the mechanical properties of materials, particularly in terms of their elastic properties. This technique is often employed in the fields of materials science, structural engineering, and quality control for various materials including metals, ceramics, composites, and polymers. ### Basic Principles: 1. **Impulse Generation**: The process begins by applying a mechanical impulse to the material or component being tested.
Incongruent melting 1970-01-01
Incongruent melting refers to a type of melting process in which a solid phase transforms into two different liquid phases or a solid phase and a gas, instead of a single liquid phase. This occurs when the composition of the solid and the liquids formed do not match. In contrast to congruent melting, where the melting solid produces a single liquid phase with the same composition as the solid, incongruent melting typically involves a complex interplay of the components present in the solid.