The Alloy M25, CuBe2Pb, offers the strength properties of Alloy 25, CuBe2, with the added benefit of being "free machining". It achieves the highest strength and hardness available among all copper alloys after age hardening, and is consequently very widely used. Delivered in the form of rod and wire, M25 is mainly used for screw-machined parts. A small addition of lead (0.2% to 0.6%) greatly improves machinability by reducing chip length and increasing tool life. Best machinability is obtained in the cold worked temper (H or TD04), which is the most commonly used temper. M25 is generally hardened after machining. It can be locally annealed to allow crimping after ageing and is easily plated. The M25 alloy is characterized by its high fatigue strength, its excellent thermal stress relaxation and by a unique combination of mechanical resistance and conductivity.

Typical uses
Thanks to its unique combination of high strength, electrical conductivity and low thermal stress relaxation, the alloy M25 is very frequently used for manufacturing machined male or female contacts in the electronics, aircraft and automotive industries. Another typical application is the production of turned parts for the watch industry.