materialI

Materiali are the substances from which objects and structures are made. They encompass a wide range of chemical compositions and microstructures, and their properties determine performance under mechanical, thermal, and chemical loads. The term covers natural materials such as wood and stone, as well as synthetic materials engineered for specific functions.

Common classifications used in science and engineering distinguish metals, polymers, ceramics, and composites. Metals generally provide high strength and ductility; polymers offer light weight and flexibility; ceramics resist heat and wear but are brittle; composites combine phases to tailor properties. Natural materials, including concrete, wood, bone, and textiles, are also widely used.

Key properties include mechanical (strength, stiffness, hardness, toughness, ductility), physical (density, melting or glass transition temperature, thermal and electrical conductivity), and chemical (corrosion resistance, chemical stability). These properties influence material selection for a given application, reliability, and lifespan.

Materials are shaped and modified by processing techniques such as casting, forming, machining, welding, and additive manufacturing. Surface treatments, coatings, and heat treatments further tailor properties like hardness, corrosion resistance, and wear behavior. Material selection often involves trade-offs among performance, cost, manufacturability, and sustainability.

Testing and standards provide quantitative data and ensure consistency across applications. Common tests measure strength, hardness, impact resistance, and fatigue behavior. Industry standards from bodies such as ISO, ASTM, and EN define procedures and acceptance criteria. Life-cycle considerations, including recyclability and environmental impact, are increasingly important in material choice.