Effect of precipitation size on dislocation density change during tensile deformation in Al-Zn-Mg alloy

To understand the strengthening mechanism of a metallic material with high dislocation density, the plastic deformation behavior of lath martensite was studied by means of in situ neutron diffraction measurements during tensile deformations using a 22SiMn2TiB steel and a Fe-18Ni alloy. The characteristics of dislocation were analyzed and were discussed with the relation of stress-strain curves. The dislocation densities (ρ) induced by martensitic transformation during heat-treatment in both materials were found to be originally as high as 1015 m-2 order, and subsequently to increase slightly by the tensile deformation. The parameter M value which displays the dislocation arrangement dropped drastically at the beginning of plastic deformation in both materials, indicating that the random arrangement became more like a dipole arrangement.

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Density change in iron after tensile deformation

phys stat sol (a) ◽

10.1002/pssa.19700020111 ◽

1970 ◽

Vol 2 (1) ◽

pp. 91-99 ◽

Cited By ~ 4

Author(s):

A. Loyer ◽

J.-M. Dorlot

Keyword(s):

Tensile Deformation ◽

Density Change

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In situ synchrotron X-ray diffraction line-profile analysis of additively manufactured Ti−6Al−4V alloy under tensile deformation

MATEC Web of Conferences ◽

10.1051/matecconf/202032103026 ◽

2020 ◽

Vol 321 ◽

pp. 03026

Author(s):

K. Yamanaka ◽

A. Kuroda ◽

M. Ito ◽

M. Mori ◽

T. Shobu ◽

...

Keyword(s):

Dislocation Density ◽

Line Profile ◽

Tensile Deformation ◽

Profile Analysis ◽

High Energy ◽

Line Profile Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Β Phase

In this study, the tensile deformation behavior of an electron beam melted Ti−6Al−4V alloy was examined by in situ X-ray diffraction (XRD) line-profile analysis. The as-built Ti−6Al−4V alloy specimen showed a fine acicular microstructure that was produced through the decomposition of the α′-martensite during the post-melt exposure to high temperatures. Using high-energy synchrotron radiation, XRD line-profile analysis was successfully applied for examining the evolution of dislocation structures not only in the α-matrix but also in the nanosized, low-fraction β-phase precipitates located at the interfaces between the α-laths. The results indicated that the dislocation density was initially higher in the β-phase and an increased dislocation density with increasing applied tensile strain was quantitatively captured in each constitutive phase. It can be thus concluded that the EBM Ti−6Al−4V alloy undergoes a cooperative plastic deformation between the constituent phases in the duplex microstructure. These results also suggested that XRD line-profile analysis combined with highenergy synchrotron XRD measurements can be utilized as a powerful tool for characterizing duplex microstructures in titanium alloys.

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297 Experimental and Polycrystal Elastoplastic Analysis of Microstructural Changes in Coarse-grained Al-Mg Alloy Caused by Large Tensile Deformation

The Proceedings of The Computational Mechanics Conference ◽

10.1299/jsmecmd.2015.28._297-1_ ◽

2015 ◽

Vol 2015.28 (0) ◽

pp. _297-1_-_297-3_

Author(s):

Yuji NAKASONE ◽

Yohei ONO ◽

Hidehiko MATSUSHITA

Keyword(s):

Tensile Deformation ◽

Elastoplastic Analysis ◽

Mg Alloy ◽

Coarse Grained ◽

Microstructural Changes

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Tensile Deformation Behaviors of Ultra-Fine Subgrained Aluminum

Materials Science Forum ◽

10.4028/www.scientific.net/msf.683.189 ◽

2011 ◽

Vol 683 ◽

pp. 189-192

Author(s):

Xiao Jing Xu ◽

Cheng Cheng ◽

Yong Luo ◽

Tao Song ◽

Zhen Dan Fei

Keyword(s):

Dislocation Density ◽

Plastic Strain ◽

Theoretical Calculation ◽

Strain Hardening ◽

High Strain ◽

Tensile Deformation ◽

Peak Stress ◽

Low Dislocation Density ◽

Deformation Behaviors ◽

Dislocation Density Increase

Tensile deformation behaviors up to peak stress of the ultra-fine subgrained aluminum (2024Al) with the subgrain sizes of about 250 nm and low dislocation density inside were investigated. The results show that the ultra-fine subgrained aluminum exhibited high strain hardening and large uniform plastic strain (19.3 %), but little post-deformation hardness/dislocation density increases (99.6 HV vs. 100.3 HV and 0.79×1014 m-2 vs. 1.03×1014 m-2, respectively). The theoretical calculation based on Taylor equation demonstrated that the dislocation density increase during the tensile deformation up to peak stress was very enormous (1.64×1015 m-2). These results not only implied that the dislocations involved in the tensile deformation were in large quantities but most of them disappeared upon the unloading of the tensile deformation, but also demonstrated that high strain hardening capacity is not a sufficient factor for ultra-fine subgrained metals to store deformation dislocations leading to post-deformation hardness increases.

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