phosphorbronze

Phosphor bronze is a family of copper-based alloys that combines tin and phosphorus with copper. In typical compositions, tin is the primary alloying element (about 5–11% by weight) and phosphorus is added in small amounts (roughly 0.4–1.0%), with the remainder being copper. The tin improves strength and hardness, while the phosphorus refines the grain and enhances wear resistance and lubricity, giving the alloy a favorable balance of stiffness, fatigue resistance, and corrosion resistance.

Phosphor bronze exhibits high strength and excellent fatigue resistance, along with good wear resistance and elasticity. It remains ductile and can be cold-worked to increase strength; it is generally machinable and has good corrosion resistance in many environments. Like other brasses and bronzes, its performance can be affected by high-temperature exposure and certain chemicals. The alloy is non-magnetic and, in many grades, retains its mechanical properties over a broad temperature range.

Processing and heat treatment: Phosphor bronze is not typically age-hardened by heat treatment. Its strength is mainly increased through cold working and can be softened by annealing. It is commonly worked by drawing, forging, and machining, and its grain structure can be tuned through appropriate processing.

Applications: The alloy is used in springs, diaphragms, electrical contacts and connectors, bearings and bushings, gears, and couplings due to its combination of stiffness, wear resistance, and elasticity. It is also well known for musical instrument strings, especially for acoustic guitars, where its bright tone and durability are valued. Additional uses include decorative hardware and marine fittings.