When purchasing a gear, there are different characteristics that you have to take into consideration to make sure you are using the best possible type of gear to power your machine. One of the most important is choosing a gear according to the type of material used to manufacture that gear. Determining the material used is important to know if it is strong and durable enough to be able to keep up with the performance the machine.
First, steel gears. These can be made up of plain carbon and stainless steel. The advantages of steel gears made up of carbon are that it is less expensive. Also, since it can be treated with heat, it is tough and hard basically it provides high strength and durability. On the downside, it has very little resistance to corrosion. On the other hand, alloy steels have high resistance to corrosion. Actually this is depending on the type of alloy steel. Austenitic steel is nonmagnetic and corrosion-resistant while martensitic steel is magnetic, easily hardened by heat and still corrosion-resistant. Moreover, production of alloy steel gears can ranged from low-grade to high-grade alloys. Steel gears are mostly used on industrial machinery.
Second, copper gears, this material is malleable and ductile, meaning it can be easily bent and shaped or molded without breaking. Because of this characteristic it easy to make copper gears out of different shapes. In addition to this, it is corrosion resistant. Most of all, it is a good conductor of electricity, that is why it is widely used in semi-conductor industries and radiators among others. Copper gears are also used to help oil pumps.
Third, cast iron gears are widely used for commercial machines like grinding mills, filter press and ice cream freezers. It has many advantages: low cost manufacturing, easy to machine (i.e. because it is made by dry cutting, has a longer cutter life and stable dimensions with a great finish), strong, hard, ductile, and has a high damping ability. However, inclusions or blowholes when manufacturing such gears are hard to detect, ultra-sonic inspection is needed.
Fourth, aluminum gears this material is made up of a metal that is lightweight, not corrosive, easy to machine because it is malleable, ductile and nonmagnetic. More than these, it functions at a maximum performance, runs smoothly, operates quietly and long-lasting. These type of gears are used in the aircraft industry and other light duty machines.
Fifth, brass gears. This type of metal is low-cost, highly resistant to corrosion, strong, hard and easy to machine. Its most important characteristic is that it is a good conductor of electricity. This type of gears are usually used on clocks, locomotive, thermal industries and other machines that needs
Lastly, powdered metal gears. Powder metal makes a high quality gear. It is operates quietly, very strong, has the ability to retain its dimensions under temperature changes and is self-lubricating. Its surface finish is excellent which allows for longer life. And a kicker for consumers, it is also inexpensive and manufacturing of gears using powder metal is effortless.
These are the commonly used types of materials when manufacturing gears. This may serve as one of your basis to make sure that the gear you are buying is compatible to the machine you are building and/ or repairing.
