Study of Corrosion-Fatigue : On a method of measuring damage caused by Corrosion-Fatigue

Abstract

After specimens were corroded with a water stream under various magnitude of rotary bending stress and for various times ; they were subjected to fatigue test in air under a stress, which is about 20% larger than the fatigue limit of the material. The numder of repetitions before fracture of the specimen was then noted and compared with that of the material undergone the same stress in air without corrosion stage. The shortening of the life was used as a criterion of the damage caused by the corrosionfatigue. The results obtained were as follows : 1. The damage rapidly increases at first, and then gradually becomes slowly. 2. Under small stress the graph decomes finally practically horizontal, under large stress, however, it reaches 100% (which means the fracture of the specimen) before becoming horizontal.