Deep Rolling Effect on Fatigue Behavior of Austenitic Stainless Steels

- Dec 24, 2016-

Deep Rolling Treatment (DRT) is a cold working process and is performed on the surface of parts that are usually previously machined.

The most important parameter to increase the hardness using DRT is the force either for AISI 304 or for AISI 316. The velocity was not found to be significant. On the other hand, with respect to roughness, the force and the velocity are the principal parameters that affect the roughness.
DRT produces an increase in the hardness, volume fraction of martensite and compressive residual stresses that increase the fatigue strength in both materials.
When both materials are deep rolled in the same conditions, the increase in hardness is greater for the AISI 304 stainless steel than the AISI 316 stainless steel. A similar situation occurs with the volume fraction of martensite, due to the differences between the materials in the staking fault energy.
At high cycles the AISI 304 presents a better fatigue response after DRT than the AISI 316. This behavior could be associated with a better resistance in fatigue crack nucleation and growth, due to metallurgical effects such as deformation twins and a greater increase in the volume fraction of martensite.