Influence of temperature and stress state on the TWIP behavior of 201LN and 316LV austenitic stainless steels

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 863; p. 144527
• Main Authors: Braga, Diogo Pedrino, Corrêa, Leonardo Muthi, Sordi, Vitor Luiz, Della Rovere, Carlos Alberto, Cintho, Osvaldo Mitsuyuki, Kliauga, Andrea Madeira
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 26-01-2023
• Subjects: Austenitic stainless steels; EBSD; Kocks-Mecking approach; SFE; TWIP effect; XRD; TWIP effect; SFE; XRD; Austenitic stainless steels; EBSD; Kocks-Mecking approach
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2022.144527

The present results analyzed deformation behavior under tension and compression of two different austenitic stainless steels: AISI 201LN, with low nickel content and stabilized with Mn and N; and AISI 316LV, stabilized with Ni and with low content of interstitial atoms. Mechanical tests were performed at a strain rate of 10−3 s−1 and at temperatures varying from −100 to 600 °C to yield comparable values of the stacking fault energy (SFE). The resulting microstructure was analyzed by X-ray diffraction and EBSD. The stress-strain curves were analyzed using the Kocks-Mecking (K-M) approach. For comparable stacking fault energies, temperature enhances the thermal activation effects that led to lower fraction of mechanical twins in the 201LN compared with the 316LV. The crystallographic re-orientation followed the flow rule irrespective of the temperature and deformation mechanism: tension and compression experiments showed the ⟨111⟩ or ⟨110⟩ orientation with the tension axis, respectively. In tension, the dislocation storage and recovery factors of the K-M model were larger than in the compression and the amount of stored dislocations and crystallite size reflect these effects. In the compression, the TWIP effect was reduced for the 316LV and suppressed for the 201LN.
•Deformation behavior under tension and compression analyses of two different AASs: the AISI 201LN and the AISI 316LV.•Different temperature ranges providing the same level of SFE for both materials.•For comparable stacking fault energies, temperature enhances the thermal activation effects.•There was a higher probability of twinning in the tensionbecause of the higher Schmid Factor and stress triaxiality.•The stress state affects the dislocation storage and recovery factors of the K-M model.