What materials are typically used in the manufacturing of gears?

The correct answer, which highlights the use of steel and aluminum alloys, reflects the materials most commonly suited for gear manufacturing due to their desirable mechanical properties. Steel, particularly alloy steels, is favored for its high strength, durability, and resistance to wear, making it suitable for high-load applications. These characteristics ensure that gears can withstand significant stresses and maintain performance over time.

Aluminum alloys, while generally lighter than steel, offer excellent machinability and corrosion resistance. They are often used in applications where weight reduction is critical, such as in aerospace and automotive industries. The combination of steel and aluminum alloys allows for a balance between strength, weight, and efficiency, which is essential in power transmission systems.

Other materials, such as plastic, rubber, copper, bronze, wood, and composites, have specific applications but do not provide the same level of performance in terms of load-bearing capacity and durability as steel and aluminum alloys do. While these alternative materials may be used in niche applications or for non-load-bearing components, they typically do not withstand the rigorous demands placed on gears in power transmission systems like those made from steel or aluminum alloys.