ON THE CAVITATION RESISTANCE OF DEEP ROLLED SURFACES OF AUSTENITIC STAINLESS STEELS

In the present work, two austenitic stainless steels (AISI 304 and AISI 316) were evaluated in cavitation tests with deep rolling treatments (DRT) on their surfaces. The results show that both steels exhibited better behaviour after the deformation process than in untreated conditions; however, the wear rate did not stabilize for the deformed surfaces due to the gradient of properties, attributed mainly to hardness profile of the material after DRT. A correlation between the cavitation erosion resistance and the fatigue strength is presented, with the cavitation wear rate and incubation time showing a good correlation with the fatigue strength coefficient in the case of high-cycle fatigue. In the case of low-cycle fatigue, a good correlation was established for the cavitation wear rate considering the Manson-Coffin theory of strain fatigue, assuming that the cavitation wear rate is inversely proportional to the fatigue life and using a fracture strain equal to the fatigue-ductility coefficient. In this case, a proportional constant around of 103 was found to establish the correlation for both steels. On the other hand, a linear correlation between the cumulative mass loss and surface roughness was separately established for steels under DRT conditions and untreated conditions. In addition, it was demonstrated that DRT is a great possible method for reducing the cost by wear.