Martensitic Phase Transformation and Deformation Behavior of Fe-Mn-C-Al Twinning-Induced Plasticity Steel during High-Pressure Torsion

The deformation mechanisms of Ti-10Mo (wt.%) alloy subjected to different quasi-hydrostatic pressure values were investigated under constrained compression using stage of high-pressure torsion apparatus. Deformation products contain {332}<113> mechanical twinning, stress-induced α″ martensitic phase and stress-induced ω phase. A volume expansion accompanied stress-induced α″ martensitic phase transformation is 2.06%. By increasing the applied pressure from 2.5 GPa to 5 GPa, the dominant deformation mechanism underwent a transition from stress-induced α″ martensitic phase transformation to {332}<113> mechanical twinning.

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Simulation of the Interaction of Plastic Deformation in Shear Bands with Deformation-Induced Martensitic Phase Transformation in the VHCF Regime

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.664.314 ◽

2015 ◽

Vol 664 ◽

pp. 314-325 ◽

Cited By ~ 3

Author(s):

Philipp Malte Hilgendorff ◽

Andrei Grigorescu ◽

Martina Zimmermann ◽

Claus Peter Fritzen ◽

Hans Jürgen Christ

Keyword(s):

Plastic Deformation ◽

Phase Transformation ◽

Deformation Behavior ◽

Shear Bands ◽

Martensitic Phase ◽

Martensitic Phase Transformation ◽

Shear Stresses ◽

Martensite Formation ◽

Microstructural Morphology ◽

Microstructural Deformation

The experimental observation of the microstructural deformation behavior of a metastable austenitic stainless steel tested at the real VHCF limit indicates that plastic deformation is localized and accumulated in shear bands and martensite formation occurs at grain boundaries and intersecting shear bands. Based on these observations a microstructure-sensitive model is proposed that accounts for the accumulation of plastic deformation in shear bands (allowing irreversible plastic sliding deformation) and considers nucleation and growth of deformation-induced martensite at intersecting shear bands. The model is numerically solved using the two-dimensional (2-D) boundary element method. By using this method, real simulated 2-D microstructures can be reproduced and the microstructural deformation behavior can be investigated within the microstructural morphology. Results show that simulation of shear band evolution is in good agreement with experimental observations and that prediction of sites of deformation-induced martensite formation is possible in many cases. The analysis of simulated shear stresses in most critical slip systems under the influence of plastic deformation due to microstructural changes contributes to a better understanding of the interaction of plastic deformation in shear bands with deformation-induced martensitic phase transformation in the VHCF regime.

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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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