Nitriding

Highest Stress Range Applications
Nitriding improves fatigue life for applications such as race engine valve springs

Nitriding is typically used in the highest stress range applications such as race engine valve springs or fuel injection springs.

Nitriding in combination with shot peening allows the fatigue life to be improved even further when compared with shot peening alone.

By defusing nitrogen into the steel surface, nitriding imparts a significant compressive residual stress into the spring outer layer.

Special high tensile alloy spring steels are used that maximise the benefit of nitriding.  With these materials the softening effect of the high temperature nitriding is reduced in the core.