# Microstructure and Texture Inhomogeneity after Large Non-Monotonic Simple Shear Strains: Achievements of Tensile Properties

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## Abstract

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## 1. Introduction

## 2. Methodology

#### 2.1. Cycles in Large Non-Monotonic Simple Shear Strains

#### 2.2. Experimental Procedure

^{2}and ~2000 respectively. EBSD maps were taken from two areas on each sample, one in the center and one 2.5 mm away from the center on the ED plane, as shown in Figure 3. Prior to EBSD analysis, the surface of the samples was polished as per the standard metallographic procedure, and followed with electrical polishing in a mixture of 300 mL of ethanol and 700 mL of phosphoric acid with a DC voltage of 2.5 V for 15 min. Grain boundaries were identified using 5° minimum disorientation angles between two adjacent pixels. Misorientations below 3° were not considered in the post-processing data procedure.

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^{−1}. Five tensile tests were performed on each sample-condition, except for the sample of sixth cycle (12th pass), from which three tests could be performed (these tensile samples was prepared from two different specimens for each pass and position). The yield stress was calculated by a 0.2% strain offset.

## 3. Results

#### 3.1. Microstructural Investigations

#### 3.2. Texture Changes

#### 3.3. Tensile Properties

_{y}) and ultimate tensile strength (UTS) of the center and the periphery of the samples of different cycles. By increasing the number of cycles, σ

_{y}and UTS increase gradually in the center region, and reach maximum values of 373 and 411 MPa, respectively, after four cycles. An approximate decrease of ~8% and 2.5% was observed in the σ

_{y}and UTS of the sample, respectively, after six cycles, which corresponds to an σ

_{y}of 343 MPa and an UTS of 400 MPa. For the periphery, σ

_{y}and UTS increased from 0 to two cycles, and thereafter decreased gradually. The maximum value of σ

_{y}and UTS in the periphery were 321 MPa and 390 MPa, respectively, which were achieved after two cycles (four passes). The amount of decrease in the σ

_{y}and UTS values from two to six cycles was ~6.5 % and 5%, respectively.

## 4. Discussions

## 5. Summary and Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Schematic representations of (

**a**) the simple shear extrusion (SSE) process, and (

**b**) the strain path during different passes of the SSE process.

**Figure 3.**Regions for the electron back-scattering diffraction (EBSD) analysis, the places where the tensile specimens were prepared from, and the dimension of the tensile samples.

**Figure 4.**TEM images and corresponding SAD patterns taken from the center and periphery after multi-cycles of the process (d is the distance from the center, and a is the side length of the initial square cross section). Red lines in the TEM images of the samples after one and two cycles indicate the boundaries of the elongated cells.

**Figure 6.**Smallest cells detected in the center and periphery of the samples after one to six cycles.

**Figure 9.**(1 0 0) pole figures of the center and the periphery of the samples after multi-cycles of the process.

**Figure 10.**Variation of (

**a**) the yield stress and ultimate tensile strength (UTS) and (

**b**) uniform elongation by increasing the non-monotonic simple shear strains in the center and the periphery.

**Figure 11.**Variation of the Taylor factor by increasing the non-monotonic simple shear strains in the center and the periphery.

**Figure 13.**A schematic representation of the change in the microstructural parameters and tensile properties of FCC materials in the center and the periphery by increasing the non-monotonic simple shear strains.

Notation | $\left\{\mathit{h}\mathit{k}\mathit{l}\right\}\langle \mathit{u}\mathit{v}\mathit{w}\rangle $ | Symbol | Crystal mimic |
---|---|---|---|

$A$ | $\left\{1\overline{1}1\right\}\langle 110\rangle $ | ||

$\overline{A}$ | $\left\{\overline{1}1\overline{1}\right\}\langle \overline{1}\overline{1}0\rangle $ | ||

${A}_{1}^{\ast}$ | $\left\{\overline{1}\overline{1}1\right\}\langle 112\rangle $ | ||

${A}_{2}^{\ast}$ | $\left\{11\overline{1}\right\}\langle 112\rangle $ | ||

$B$ | $\left\{1\overline{1}2\right\}\langle 110\rangle $ | ||

$\overline{B}$ | $\left\{\overline{1}1\overline{2}\right\}\langle \overline{1}\overline{1}0\rangle $ | ||

$C$ | $\left\{001\right\}\langle 110\rangle $ |

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**MDPI and ACS Style**

Bagherpour, E.; Qods, F.; Ebrahimi, R.; Miyamoto, H.
Microstructure and Texture Inhomogeneity after Large Non-Monotonic Simple Shear Strains: Achievements of Tensile Properties. *Metals* **2018**, *8*, 583.
https://doi.org/10.3390/met8080583

**AMA Style**

Bagherpour E, Qods F, Ebrahimi R, Miyamoto H.
Microstructure and Texture Inhomogeneity after Large Non-Monotonic Simple Shear Strains: Achievements of Tensile Properties. *Metals*. 2018; 8(8):583.
https://doi.org/10.3390/met8080583

**Chicago/Turabian Style**

Bagherpour, Ebad, Fathallah Qods, Ramin Ebrahimi, and Hiroyuki Miyamoto.
2018. "Microstructure and Texture Inhomogeneity after Large Non-Monotonic Simple Shear Strains: Achievements of Tensile Properties" *Metals* 8, no. 8: 583.
https://doi.org/10.3390/met8080583