Effect of Strength on Corrosion Fatigue Performance 1

Hi,

The fatigue limit of a steel that was heat treated in order to obtain 1000 MPa (tensile stregth) can reduce 4 or 5 times if this material work in a corrosive environment.

Margaria

Carburize,

The important factor to consider is presence of a flaw. In the absence of a large flaw, the majority of fatigue life is spent in the fatigue crack initiation process. High strength hinders the nucleation of critical fatigue cracks. However, in the presence of a large flaw, high strength is detrimental to fatigue crack propagation because the process zone is smaller and absorbs less energy.

In a corrosive environment, it is possible to initiate flaws such as pits, subsurface hydrogen cracks, etc. Thus, it is likely that high-strength materials will have inferior corrosion fatigue performance.

Regards,

Cory

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