The Influence of Forming and Corrosion on the Fatigue Behaviour of Automotive Steels

A study has been made of the influence of press forming and corrosion under cars on the fatigue properties of sheet steels. Press forming was done in the laboratory and corresponded to types of deformation occurring in production. Samples from laboratory and undervehicle corrosion environments were tested.

Forming was found to improve fatigue properties and corrosion to cause a deterioration. The drop in fatigue strength caused by corrosion was similar for all types of steel examined, and no worse than that caused by moderate notches that are commonly encountered in service.