Study of Crystallographic Texture Evolution during High-Temperature Deformation of 18Cr-ODS Ferritic Steel based on Plasticity Assessment

AbstractThis paper aims at understanding the texture evolution in extruded oxide dispersion strengthened 18Cr ferritic steel during high-temperature uniaxial compression testing at 1,423 K at a strain rate of 0.01/s based on extensive electron back scatter diffraction characterization. The α-fiber texture is observed along the extrusion direction (ED) in the initial microstructure. The flow curves generated during uniaxial compression test are used to determine the associated hardening parameters. In addition, the degree of texture evolution after deformation along the ED and the transverse direction (TD) with respect to the initial condition has been predicted using VPSC-5 constitutive model. The prediction shows that the deformation along the ED produces a dominant γ-fiber texture in contrast to the TD. This is in agreement with the experimental results where γ-fiber texture is observed, due to enhanced dynamic recrystallization at high-temperature deformation.

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Analysis of Intragranular Misorientation Related to Deformation in an Al-Mg-Mn Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.495-497.1049 ◽

2005 ◽

Vol 495-497 ◽

pp. 1049-1054 ◽

Cited By ~ 22

Author(s):

Yoshimasa Takayama ◽

Jerzy A. Szpunar ◽

Hajime Kato

Keyword(s):

Electron Microscope ◽

High Temperature ◽

Room Temperature ◽

Electron Back Scatter Diffraction ◽

High Temperature Deformation ◽

Temperature Deformation ◽

Stored Energy ◽

Kernel Average Misorientation ◽

Dislocation Glide ◽

Scanning Electron

Intragranular misorientation reflects strain generated during deformation with dislocation glide. The SEM/EBSP (scanning electron microscope/ electron back scatter diffraction pattern) technique provides is “kernel average misorientation (KAM)” as the most appropriate quantity to evaluate the strain or the stored energy for a given point. The KAM is defined for a given point as the average misorientation of that point with all of its neighbors. In the present paper two analyses of the intragranular misorientation using the SEM/EBSP technique for a cyclic deformation at room temperature and a high temperature deformation in an Al-Mg-Mn alloy are reviewed.

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Effect of Grain Boundary Migration on Texture Formation in Al-3mass%Mg Solid Solution during High Temperature Deformation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.558-559.551 ◽

2007 ◽

Vol 558-559 ◽

pp. 551-556 ◽

Cited By ~ 2

Author(s):

Kazuto Okayasu ◽

Hiroki Takekoshi ◽

Hiroshi Fukutomi

Keyword(s):

Solid Solution ◽

High Temperature ◽

Grain Boundary ◽

Boundary Migration ◽

Fiber Texture ◽

High Temperature Deformation ◽

Temperature Deformation ◽

Grain Boundary Migration ◽

Strain Rates ◽

Main Component

Uniaxial compression deformation is conducted on solid solution Al-3mass%Mg and Al-3mass%Mg-0.2mass%Sc with Al3Sc precipitates in the strain rates ranging from 1.0×10-4s-1 to 5.0×10-3s-1 at 723K. High temperature yielding is observed. Fiber texture is constructed in all the deformation conditions. While the main component of the fiber texture changes from {011} to {001} in Al-3mass%Mg alloy with an increase in strain rate, no big change in texture main component is seen for Al-3mass%Mg-0.2mass%Sc alloy with Al3Sc precipitates. It is experimentally shown that the development of {001} fiber texture can be attributed to the grain boundary migration.

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Effect of Large Strain on Texture Formation Behavior of AZ80 Magnesium Alloy during High Temperature Deformation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.938 ◽

2016 ◽

Vol 879 ◽

pp. 938-942 ◽

Cited By ~ 1

Author(s):

Kwon Hoo Kim ◽

Kazuto Okayasu ◽

Hiroshi Fukutomi

Keyword(s):

High Temperature ◽

Magnesium Alloy ◽

Uniaxial Compression ◽

High Temperature Deformation ◽

Temperature Deformation ◽

Deformation Condition ◽

Basal Texture ◽

Compression Deformation ◽

Az80 Magnesium Alloy ◽

Formation Behavior

In previous study, the formation behavior of texture and microstructure in AZ80 magnesium alloy under high temperature deformation was investigated. It was found that the basal texture was formed at stress of more than 15-20MPa and the non-basal texture was formed at stress of less than 15-20MPa. This means that stress of 15-20MPa is the change point of deformation mechanism. Therefore, in this study, uniaxial compression deformation of AZ80 magnesium alloy was carried out at high temperature deformation (stress of 15-20MPa). Behaviors of microstructure and texture development are experimentally studied. The material used in this study is a commercial magnesium alloy extruded AZ80. The uniaxial compression deformation is performed at temperature of 723K and strain rate 3.0×10-3s-1, with a strain range of between-0.4 and-1.3. Texture measurement was carried out on the compression planes by the Schulz reflection method using nickel filtered Cu Kα radiation. EBSD measurement was also conducted in order to observe spatial distribution of orientation. As a result of high temperature deformation, the maximum value of the flow stress is observed at the true stress-strain curves, and the main component of texture and the accumulation of pole density vary depending on deformation condition.

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