How to Choose Gear Heat Treatment? Five Heat Treatment Processes Explained in One Article

Hard tooth surfaces and a tough core – these are the standards for good gears. Heat treatment is the magic to achieve this. Choosing the right process makes a world of difference in performance and lifespan.

In the production of worm gears (WMRV) and helical gearboxes (WR/WK/WF/WS), heat treatment of parts is essential. Here are some common heat treatment methods:

Normalizing

Purpose: Post-forging/casting "microstructure preparation," refining grain size and improving machinability.

Simply put: Paves the way for subsequent machining and heat treatment, or is used for gears with less demanding requirements.

Quenching and Tempering
Purpose: Quenching followed by high-temperature tempering to obtain a strong and tough core.

Simply put: Creates the "strong and tough inner core" of gears, an essential preparatory process for heavy-duty gears.

Surface Hardening
Purpose: Heating only the tooth surface and rapidly cooling to achieve an outer hardness and inner toughness.

Simply put: The most common solution for medium-hard tooth surfaces, highly efficient with minimal deformation.

Carburizing and Quenching
Purpose: Allows carbon to "eat" into the surface of low-carbon steel before quenching, resulting in an extremely hard surface layer and an extremely tough core.

Simply put: The gold standard for heavy-duty, high-speed, and impact-prone gears (such as automotive transmission gears).

Nitriding
Purpose: Allows nitrogen to penetrate the surface at low temperatures, achieving ultra-high hardness, wear resistance, and corrosion resistance.

Simply put: Minimal deformation, suitable for precision gears, complex gears, and corrosive environments.

Would you like to know more about gear reducers? leave me a message.