IS 292 covers phosphor bronze — a Cu-Sn-P alloy known for excellent spring properties, fatigue resistance, and corrosion resistance. Used for springs, electrical contacts, bearings, gears, and bellows where both strength and corrosion resistance are needed.
Specification for phosphor bronze ingots and castings covering grades, chemical composition, mechanical properties, and quality requirements.
Key Values
PB2 tin content9-11%
PB2 phosphorus0.1-0.35%
PB2 tensile strengthMin 250 MPa
Practical Notes
! Phosphor bronze is preferred over brass for springs because of much higher fatigue strength.
! The phosphorus content (0.1-0.35%) acts as a deoxidizer and improves castability and strength.
! PB2 is the most commonly used grade for general bearings and spring applications.