Concurrent microstructural evolution of ferrite and austenite in a duplex stainless steel processed by high-pressure torsion

The duplex stainless steel 2205, designated DSS2205 and having a duplex structure comprising ferrite and austenite phases, was processed by high-pressure torsion (HPT) and the microstructural and hardness evolutions were investigated after various HPT revolutions and at different positions within the specimens. The results show that the grain refinement induced by severe deformation processing is different in the ferrite and austenite phases such that the ferrite grains are refined via dislocation subdivision, whereas grain refinement in the austenite phase depends mainly on the interaction of dislocations and twin boundaries at relatively low strains. When the numbers of revolutions increases, the grain refinement in austenite restricts the occurrence of deformation twinning so that dislocation slip becomes dominant. During HPT processing, the effect of the phase boundaries on the mechanical properties of the alloy is very significant. The results show the average width between two adjacent phases and the hardness of the alloy are generally consistent with the classical Hall–Petch relationship.

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Factors Influencing the Shearing Patterns in High-Pressure Torsion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.45 ◽

2014 ◽

Vol 783-786 ◽

pp. 45-50 ◽

Cited By ~ 1

Author(s):

Yi Huang ◽

Megumi Kawasaki ◽

Terence G. Langdon

Keyword(s):

High Pressure ◽

Stainless Steel ◽

Duplex Stainless Steel ◽

High Pressure Torsion ◽

Processing Technique ◽

Model Material ◽

Two Phase ◽

Factors Influencing

High-pressure torsion (HPT) is a processing technique in which samples are subjected to a high pressure and torsional straining. Experiments show that the shearing patterns in HPT are dependent upon the alignment of the anvils within the HPT facility. Using a two-phase duplex stainless steel as a model material, experiments were conducted by placing the anvils in different amounts of initial misalignment. The results demonstrate the importance of always ensuring that the upper and lower anvils are in good alignment prior to HPT processing.

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Microstructure, phase composition and hardness evolution in 316L stainless steel processed by high-pressure torsion

Materials Science and Engineering A ◽

10.1016/j.msea.2016.01.057 ◽

2016 ◽

Vol 657 ◽

pp. 215-223 ◽

Cited By ~ 36

Author(s):

Jenő Gubicza ◽

Moustafa El-Tahawy ◽

Yi Huang ◽

Hyelim Choi ◽

Heeman Choe ◽

...

Keyword(s):

High Pressure ◽

Stainless Steel ◽

Phase Composition ◽

316L Stainless Steel ◽

High Pressure Torsion

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Magnetic Characterization of SUS316L Deformed by High Pressure Torsion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.1300 ◽

2011 ◽

Vol 239-242 ◽

pp. 1300-1303

Author(s):

Hong Cai Wang ◽

Minoru Umemoto ◽

Innocent Shuro ◽

Yoshikazu Todaka ◽

Ho Hung Kuo

Keyword(s):

Plastic Deformation ◽

High Pressure ◽

Stainless Steel ◽

Phase Transformation ◽

Austenitic Stainless Steel ◽

Volume Fraction ◽

High Pressure Torsion ◽

Austenitic Matrix ◽

Magnetic Characterization

SUS316L austenitic stainless steel was subjected to severe plastic deformation (SPD) by the method of high pressure torsion (HPT). From a fully austenitic matrix (γ), HPT resulted in phase transformation from g®a¢. The largest volume fraction of 70% a¢ was obtained at 0.2 revolutions per minute (rpm) while was limited to 3% at 5rpm. Pre-straining of g by HPT at 5rpm decreases the volume fraction of a¢ obtained by HPT at 0.2rpm. By HPT at 5rpm, a¢®g reverse transformation was observed for a¢ produced by HPT at 0.2rpm.

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