materialsmetal

Materialsmetal is a nonstandard term used here to refer to metals and metal-based materials used in engineering and manufacturing. Metals are typically crystalline materials bonded by metallic bonds, which confer electrical and thermal conductivity, ductility, reflectivity, and the ability to deform under stress without fracturing. They are commonly categorized into ferrous metals (iron and its alloys, notably steel and cast iron) and nonferrous metals (such as aluminum, copper, nickel, zinc, titanium, and their alloys). Alloys are engineered combinations designed to achieve specific properties, such as greater strength, hardness, or corrosion resistance.

Structure and properties: Metals exhibit crystalline or polycrystalline microstructures with crystal lattices that influence mechanical behavior. Common lattice types include body-centered cubic, face-centered cubic, and hexagonal close-packed arrangements. Properties such as strength, ductility, toughness, density, and electrical and thermal conductivity depend on composition, grain size, impurities, and defect structures. Heat treatment, cold working, and alloying are used to modify these properties.

Processing and production: Metal production begins with ore extraction and refinement, followed by alloying. Shaping methods include casting, forging, rolling, extrusion, and welding. Finishing processes such as heat treatment, surface hardening, plating, and coating enhance wear resistance and corrosion resistance. Additive manufacturing of metals is an expanding field, enabling complex geometries and rapid prototyping.

Applications and sustainability: Metals are foundational in construction, transportation, energy, and electronics. They offer a combination of strength-to-weight and durability that supports heavy machinery and infrastructure. Recycling of metal scrap is economically important and reduces energy use and resource depletion. Ongoing research emphasizes developing lighter, stronger alloys, corrosion-resistant materials, and processes that reduce environmental impact.