materiały: High-entropy alloy

Evidence: 100 • authority: 72

High-entropy alloys (HEAs) are alloys that are formed by mixing equal or relatively large proportions of (usually) five or more elements. Prior to the synthesis of these substances, typical metal alloys comprised one or two major components with smaller amounts of other elements. For example, additional elements can be added to iron to improve its properties, thereby creating an iron-based alloy, but typically in fairly low proportions, such as the proportions of carbon, manganese, and others in various steels. Hence, high-entropy alloys are a novel class of materials. The term "high-entropy alloys" was coined by Taiwanese scientist Jien-Wei Yeh because the entropy increase of mixing is sub…

Evidence: 63 • authority: 92

Development Status of Fe-V-Based High-Entropy Alloys for Nuclear Reactors.. Against the backdrop of the "dual carbon" strategy, clean and efficient energy is the goal that people pursue. Nuclear fusion energy is recognized as a clean energy source worldwide. Due to the high-energy neutrons produced during nuclear fusion reactions, the materials for nuclear fusion reactors are required to be low in activation while also having high resistance to irradiation damage. Both Fe and V are completely low-activation elements, and high-entropy alloys currently exhibit excellent radiation resistance properties. Therefore, Fe-V-based high-entropy alloys may become a competitive candidate material for f…

Evidence: 55 • authority: 92

High-Entropy Alloys: A Review of Emerging Sensing Materials for Next-Generation Flexible Electronics.. High-entropy alloys (HEAs), composed of five or more principal elements in near-equimolar ratios, have emerged as a groundbreaking class of materials for next-generation flexible electronics. This review systematically examines the unique potential of HEAs as sensing materials, moving beyond their traditional role as structural components. We first elucidate the fundamental mechanisms-core effects including lattice distortion, sluggish diffusion, and the cocktail effect-that endow HEAs with an exceptional synergy of high strength, good ductility, tunable electrical resistivity, and superio…

Evidence: 48 • authority: 72

Materials science is an interdisciplinary field concerned with understanding the relationships between the structure of materials and their properties and using this knowledge to design materials for specific applications. The internal structure of a material—from atomic arrangements to microscopic features—strongly influences its mechanical, electrical, thermal, and optical behavior. In engineering practice, materials science and engineering are often described through the processing–structure–properties–performance paradigm, in which processing determines structure, structure determines properties, and properties ultimately control the performance of a material in service. The intellectua…

Evidence: 48 • authority: 72

Elastocaloric materials are a class of advanced materials. These materials show a substantial change in temperature when mechanical stress is applied and then removed. This phenomenon, known as the elastocaloric effect, is the reversible thermal response of the material to mechanical loading and unloading. The effect is often caused by changes in entropy within the material's structure. This can be due to phase transformations or reorientation of crystalline domains. Unlike conventional materials, elastocaloric materials can experience substantial temperature changes under mechanical stress. This makes them promising for solid-state refrigeration and heating applications. The relevance of e…

Evidence: 48 • authority: 72

A metal (from Ancient Greek μέταλλον (métallon) 'mine, quarry, metal') is a material that, when polished or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. These properties are all associated with having electrons available at the Fermi level, as opposed to nonmetallic materials which do not. Metals are typically ductile (can be drawn into a wire) and malleable (can be shaped via hammering or pressing). A metal may be a chemical element, such as iron, an alloy, such as stainless steel, or a molecular compound, such as polymeric sulfur nitride. The general science of metals is called metallurgy, a subtopic of materials science; aspects of their elec…

Evidence: 41 • authority: 80

Development of cost-effective high-entropy alloys with superior mechanical properties

Evidence: 41 • authority: 80

Mechanical and Structural Properties of High Entropy Alloys

Evidence: 41 • authority: 80

Microstructure and Mechanical Properties of High Entropy Alloys

Evidence: 41 • authority: 92

Entropy-driven densification of medium-entropy alloys with laser powder bed fusion.. Anomalies inherent to laser-based additive manufacturing (AM), including porosity and structural defects, present significant barriers to fabricating high-integrity metallic structural components. These unavoidable anomalies can significantly degrade the long-term properties of metals, including fatigue, creep, and corrosion, thereby limiting their use in critical environments. In this study, we overcome this challenge with a single-step entropy engineering strategy. By integrating CoCrNi and 316 L powders and enabling temporal changes in entropy evolution during printing, we obtained a nearly void-free (de…

Evidence: 41 • authority: 92

Understanding the role of entropy in designing high-performance thermoelectrics.. The design of high-entropy alloys is effective in lowering thermal conductivity but often reduces carrier mobility, thereby limiting electrical transport properties. Understanding the relationship among configurational entropy, thermal conductivity, and carrier mobility in high-entropy alloys is critical for enhancing thermoelectric performance. We demonstrate that a systematic and substantial increase in configurational entropy in half-Heusler alloys leads to an asymptotic reduction of lattice thermal conductivity. The reduced phonon group velocity and enhanced phonon scattering induced by atomic-scale chemic…

Evidence: 41 • authority: 72

An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although the word is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties that differ from those of the pure elements from which they are made. The vast majority of metals used for commercial purposes are alloyed to improve their properties or behavior, such as increased strength, hardness or corrosion resistance. Metals may also be alloyed to reduce their overall cost, for instance alloys of gold and copper. In an alloy, the atoms are joined by metallic bonding rather than by covalent bonds typically found in chemica…