The influence of plastic deformation on lattice defect structure and mechanical properties of 316L austenitic stainless steel

Authors: El-Tahawy, M., Gubicza, J., Huang, Y., Choi, H., Choe, H., Lábár, J.L. and Langdon, T.G.

Journal: Materials Science Forum

Volume: 885

Pages: 13-18

eISSN: 1662-9752

ISSN: 0255-5476

DOI: 10.4028/www.scientific.net/MSF.885.13

Abstract:

The effect of different plastic deformation methods on the phase composition, lattice defect structure and hardness in 316L stainless steel was studied. The initial coarse-grained γ-austenite was deformed by cold rolling (CR) or high-pressure torsion (HPT). It was found that the two methods yielded very different phase compositions and microstructures. Martensitic phase transformation was not observed during CR with a thickness reduction of 20%. In γ-austenite phase in addition to the high dislocation density (~10 × 1014 m-2) a significant amount of twin-faults was detected due to the low stacking fault energy. On the other hand, γ-austenite was gradually transformed into ε and α’-martensites with transformation sequences γ→ε→α’ during HPT deformation. A large dislocation density (~133 × 1014m-2) was detected in the main phase (α’-martensite) at the periphery of the disk after 10 turns of HPT. The high defect density is accompanied by a very small grain size of ~45 nm in the HPT-processed sample, resulting in an very large hardness of 6130 MPa.

Source: Scopus

The influence of plastic deformation on lattice defect structure and mechanical properties of 316L austenitic stainless steel

Authors: El-Tahawy, M., Gubicza, J., Huang, Y., Choi, H., Choe, H., Lábár, J.L. and Langdon, T.G.

Conference: 10th Hungarian Conference on Materials Science

Dates: 11 October-13 March 2015

Journal: Materials Science Forum

Volume: 885

Pages: 13-18

eISSN: 1662-9752

ISBN: 9783038357636

ISSN: 0255-5476

DOI: 10.4028/www.scientific.net/MSF.885.13

Abstract:

© 2017 Trans Tech Publications, Switzerland. The effect of different plastic deformation methods on the phase composition, lattice defect structure and hardness in 316L stainless steel was studied. The initial coarse-grained γ-austenite was deformed by cold rolling (CR) or high-pressure torsion (HPT). It was found that the two methods yielded very different phase compositions and microstructures. Martensitic phase transformation was not observed during CR with a thickness reduction of 20%. In γ-austenite phase in addition to the high dislocation density (~10 × 1014 m-2) a significant amount of twin-faults was detected due to the low stacking fault energy. On the other hand, γ-austenite was gradually transformed into ε and α’-martensites with transformation sequences γ→ε→α’ during HPT deformation. A large dislocation density (~133 × 1014m-2) was detected in the main phase (α’-martensite) at the periphery of the disk after 10 turns of HPT. The high defect density is accompanied by a very small grain size of ~45 nm in the HPT-processed sample, resulting in an very large hardness of 6130 MPa.

Source: Manual

Preferred by: Yi Huang