Understanding Heat Treatment in Bearing Manufacturing

Key Takeaways:

• Heat treatment for bearings can increase hardness or ductility depending on requirements.
• Bearing manufacturers rely on controlled heat treatment to ensure durability and long-term performance.

For any bearing manufacturing company, precision and reliability start at the metallurgical level. One of the most critical processes in bearing production is heat treatment, a controlled thermal cycle that directly affects hardness, stability, and long-term performance. At Delta Centrifugal®, we support bearing manufacturers with high-quality materials designed to withstand the demands of this rigorous process.

Why Heat Treatment Matters

Heat treatment for bearings is essential to achieve the hardness and wear resistance required in high-speed or high-load applications. In its initial state, bearing steel is soft and easily machinable. To harden the material, we normalize it at about 1900°F this resets the grain structure of the material and relieves any stresses to the material caused during the casting process. This sets the stage for hardening in the quench phase. Quenching is a rapid cooling process that essentially “locks” the crystalline structure of the metal in place and hardens it significantly. This can cause warping and cracking is not done with precision. So it is of utmost importance to have a rigorously controlled heat treat process.

Stabilizing for Precision

In a normalized and quenched state our bearing steel is exceptionally hard, but it is extremely brittle. This means that instead of holding up under extreme pressures, materials will crack or shatter. We improve material ductility and toughness by tempering the material. This is accomplished by heating the material in a controlled fashion below its lowest critical temperature, holding for a set time and slowly allowing the material to cool down.

Full-Service Support for Precision Bearing Components

Delta Centrifugal® provides bearing manufacturers with centrifugally cast components engineered for dimensional stability and high-performance applications. With in-house heat-treating capabilities — including annealing, normalizing, quenching, tempering and everything in between — we ensure that our bearing-grade materials meet the exacting requirements of hardness, strength, and long-term dimensional control. From casting through heat treatment, and beyond we offer a vertically integrated solution for customers who demand precision and reliability.