3. Residual stresses – Significance

Mechanical treatments such as shot-peening, roller burnishing and rolling (sometimes in addition to heat treatment) are obviously operations that generate compressive stresses on the surface.

Hardening by quenching (on previously case-hardened or carbonitrided base steel), nitriding and hardening by quenching after surface heating generally lead to compressive stresses on the surface of the steel or cast iron (figure 6 case of case-hardening + direct quenching).

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