Which is the best metal for gears?

The materials that are used for the manufacturing of the gears are based on the service conditions and strength. Cast iron is the most frequent material for gears due to its high wearing properties, ease in producing complicated shapes, and machinability. Phosphor bronze is used for worm gears due to the wear resistance ability of the material.

Alloy or carbon metals are used due to their high values of strength. Alloys like steels are heated to achieve an ideal combination of hardness and toughness. Hardness is one of the most important factors in the design of gear.