Glossary

An alloy is a metal-based material made by combining two or more chemical elements (at least one of them a metal) to create a material with engineered properties that you usually can’t get from a pure metal alone. Think of it like “recipe metallurgy”: you start with a base metal (iron, aluminum, copper, nickel, titanium, etc.), then add specific elements in controlled amounts to dial in strength, toughness, corrosion resistance, heat resistance, machinability, or wear resistance.

Alloys work because the added elements change the metal’s internal structure. Some atoms dissolve into the base metal’s crystal lattice (solid solution strengthening), some form tiny hard particles (precipitates) that block deformation, and some create distinct phases that change how the metal behaves under load or temperature. Heat treatment often matters as much as chemistry—many alloys are designed so their microstructure can be “set” by quenching/tempering, aging, annealing, or solution treating.

In the fastener world, alloys are the reason we can have a bolt that’s tough and ductile for impact, another that’s high-strength for clamping, and another that laughs at chlorides and high heat. Ferrous alloys (iron-based) include carbon steel, alloy steel, and stainless steel—your everyday bolts, structural fasteners, and corrosion-resistant grades. Non-ferrous alloys include aluminum alloys (lightweight), copper alloys (conductive/corrosion-resistant), nickel alloys (high-temperature/corrosive service), and titanium alloys (high strength-to-weight and excellent corrosion resistance). In short: an alloy is how we turn “a metal” into “the right metal for the job.”