alliage

Alliage is the French term for alloy. In materials science, an alloy is a substance composed of two or more elements, where at least one is a metal, designed to obtain properties superior to the constituent elements, such as greater strength, hardness, or resistance to corrosion.

Alloys can be homogeneous, forming a single-phase solid solution, or heterogeneous, containing distinct phases. Common elements include carbon, chromium, vanadium, nickel, and others, which are combined with base metals like iron or aluminum.

Production methods include melting and combining elements (fusion), mechanical alloying, and powder metallurgy, or diffusion-driven solid-state reactions. The choice depends on desired properties and cost.

Notable examples: steel (iron with carbon and other elements), bronze (copper with tin), brass (copper with zinc). Aluminum alloys (aluminum with magnesium, silicon, or zinc) and titanium alloys (titanium with aluminum, vanadium) are widely used.

Applications span structural components, tools, machinery, automotive and aerospace hardware, electronics, and consumer goods. Alloys are engineered to balance strength, weight, hardness, and corrosion resistance.

History notes that alloying dates back to ancient times, with bronze among the earliest widely used alloys, followed by iron and steel developments that shaped modern metallurgy.