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Engineering

Plasma Nitriding: Enhancing the Wear Resistance of Steel Gears

Quick fact

Plasma nitriding can create a case-hardened layer on steel gears that is up to 70% harder than the core, yet the process occurs at temperatures low enough (around 500°C) that the gear geometry remains essentially unchanged—no distortion, no re-machining needed.

Why this is interesting

Steel gears in a car gearbox can grind and wear out after thousands of miles—but some gears last far longer without extra bulk. How can a thin surface layer make such a dramatic difference?