Ferritic Temperature: Key to Low-Distortion Heat Treatment

A metal component inside a plasma nitriding chamber, treated at ferritic temperature to enhance wear resistance while maintaining core toughness.

The term "ferritic temperature" refers to the thermal range from room temperature up to 723°C (1333°F), within which steels and certain alloys maintain their crystalline atomic structure, preserving their ductility and mechanical strength.

Iron-carbon (Fe-C) equilibrium diagram highlighting the ferritic temperature range in plasma nitriding.

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Unlike conventional heat treatments, plasma nitriding, a thermochemical process, operates at temperatures between 350°C and 600°C (662°F - 1112°F), meaning it remains within the ferritic range.

This is why parts treated with plasma nitriding experience virtually no distortion and rarely require post-treatment grinding, even those with complex geometries. Since the material remains below the austenitization threshold, its crystalline structure remains unchanged, ensuring dimensional stability.

It is important to note that titanium components are an exception in terms of processing temperature. Due to their unique diffusion behavior and material characteristics, they require higher temperatures—up to 850°C (1562°F)—for effective nitriding, even though phase transformation is not involved.