Details

Autor(en) / Beteiligte

• Hamada, A.S.
• Karjalainen, L.P.
• Surya, P.K.C. Venkata
• Misra, R.D.K.

Titel

Fatigue behavior of ultrafine-grained and coarse-grained Cr–Ni austenitic stainless steels

Ist Teil von

• Materials science & engineering. A, Structural materials : properties, microstructure and processing, 2011-04, Vol.528 (10), p.3890-3896

Ort / Verlag

Kidlington: Elsevier B.V

Erscheinungsjahr

2011

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• ► Fatigue resistance of ultrafine-grained 301LN is highly increased by grain refinement. ► Fatigue mechanism differs distinctly from that of coarse-grained steel. ► Grain boundary cracking is intensive in ultrafine-grained steel. ► Cyclic hardening is minimal in ultrafine-grained steel compared to that in coarse-grained one High-cycle bending fatigue behavior of an ultrafine-grained Cr–Ni Type 301LN austenitic stainless steel, obtained by reversion annealing, was investigated and compared to that of the conventional coarse-grained counterpart. The fatigue limit was significantly increased from 350 MPa to 630 MPa, reaching 59% of the tensile strength, a behavior attributed to grain refinement. Fatigue cycling resulted in hardness increments that were very different between these structures; in the coarse-grained steel 47%, but only 6–10% in the ultrafine-grained steel. The fatigue damage was observed to occur by grain boundary cracking in the ultrafine-grained steel, while mostly by slip band formation and crack propagation along these slip bands and grain boundaries in the coarse-grained counterpart. Dislocation structures observed reflected these pronounced differences in the cyclic behavior.