Grain Refinement and Texture Evolution in AZ31 Alloy during ECAP Process and Their Effects on Mechanical Properties

2005 ◽  
Vol 475-479 ◽  
pp. 549-554 ◽  
Author(s):  
H.S. Kim ◽  
Hyo Tae Jeong ◽  
Ha Guk Jeong ◽  
Woo Jin Kim
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Grain Refinement ◽  
Texture Evolution ◽  
Az31 Alloy ◽  
Mg Alloys ◽  
Fine Grained ◽  
Ecap Process ◽  
Texture Modification ◽  
Similar Texture

The softening of fine-grained ECAPed AZ31 Mg alloys could be ascribed to the texture modification during ECAP. Lower ECAP temperature is more effective in refining the microstructure. The strength of the ECAPed AZ 31 Mg alloys increased with decrease in grain size when they have similar texture.

Mechanical Properties and Texture Evolution of AZ31 Mg Alloy during Equal Channel Angular Pressing

2005 ◽  
Vol 475-479 ◽  
pp. 545-548 ◽  
Author(s):  
Hyo Tae Jeong ◽  
Woo Jin Kim
Keyword(s):  
Mechanical Properties ◽  
Grain Refinement ◽  
Equal Channel Angular Pressing ◽  
Texture Evolution ◽  
Fiber Texture ◽  
Mg Alloy ◽  
Angular Pressing ◽  
Ecap Process ◽  
Az31 Mg Alloy ◽  
Similar Texture

Microstructure and texture evolution in the AZ31 Mg alloy subject to equal channel angular pressing (ECAP) have been investigated and correlated with the mechanical properties. When AZ31 Mg alloy was ECAPed up to 8 passes following the route Bc, grain refinement occurred effectively. Texture was also changed during ECAP. The original fiber texture of the extruded AZ31 Mg alloy changed to a new texture component of ] 1 3 2 5 )[ 1 1 01 ( , and the texture of ] 1 3 2 5 )[ 1 1 01 ( orientation was rotated to ] 0 2 5 7 )[ 6 4 13 ( orientation after 6-pass ECAP process. The variation of the strength with the pass number was explained by the texture and grain size. The strength data of AZ31 Mg alloys followed the standard Hall-Petch relationship when the similar texture was retained during the ECAP process. Otherwise the effect of texture on strength was dominant over the strengthening due to grain refinement.

scholarly journals Applying Hybrid Equal Channel Angular Pressing (HECAP) to pure copper using optimized Exp.-ECAP die

2021 ◽  
Author(s):  
Serkan Öğüt ◽  
Hasan Kaya ◽  
Aykut Kentli ◽  
Mehmet UÇAR
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Grain Refinement ◽  
Equal Channel Angular Pressing ◽  
Pure Copper ◽  
Mechanical Tests ◽  
Geometric Parameters ◽  
Homogeneous Distribution ◽  
Angular Pressing ◽  
Ecap Process

Abstract Equal channel angular pressing (ECAP), expansion equal channel angular pressing (Exp.-ECAP) and hybrid equal channel angular pressing (HECAP) processes were applied to pure copper specimens within this study. Before the ECAP and HECAP processes, an Exp.-ECAP mold with optimum geometric parameters was produced to be used in these processes. The samples, on which ECAP, Exp.-ECAP and HECAP processes were applied, were subjected to microstructure analysis and mechanical tests, and the effects of these processes were examined. The results obtained showed that the Exp.-ECAP process gave better results in grain refinement and mechanical properties, and the Exp.-ECAP passes applied after the ECAP process within the scope of the HECAP process provided a more homogeneous distribution for grain size and hardness.

Microstructure and Texture Evolution of Cross Rolled AZ31 Mg Sheet

2008 ◽  
Vol 41-42 ◽  
pp. 435-438 ◽  
Author(s):  
Dae Guen Kim ◽  
Hyeon Taek Son ◽  
Jae Seol Lee
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Large Strain ◽  
Texture Evolution ◽  
Mg Alloys ◽  
Planar Anisotropy ◽  
Rolled Sample ◽  
The Press ◽  
R Value ◽  
Press Formability

The aims of this study are to investigate the microstructure evolution of AZ31 Mg alloys with normal rolling and cross rolling as the large strain hot rolling affects microstructure, texture and mechanical properties of AZ31 Mg alloys. In the microstructures of as-rolled both samples, twins are clearly apparent, small and recrystallized grains are visible along some grain boundary and twinned regions. The Lankford values of large strain cross rolled sample obviously demonstrate the higher average r-value and lower planar anisotropy value. The press formability of cross rolled Mg alloy might be improved due to control of texture and grain size by severe deformation.

Production of Fine-Grained and Weak Texture Structure in an Mg-7Gd-5Y-1Nd-0.5Zr Alloy by Multi-Axial Forging

2014 ◽  
Vol 633-634 ◽  
pp. 120-124
Author(s):  
Ting Li ◽  
Kui Zhang ◽  
Zhi Wei Du ◽  
Jia Wei Yuan ◽  
Xing Gang Li
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Texture Evolution ◽  
Ultrafine Grain ◽  
Fine Grained ◽  
Fine Grain ◽  
Ultrafine Grain Size ◽  
Refinement Mechanism ◽  
Texture Structure ◽  
Weak Texture

Multi-axial forging was employed to produce simultaneously ultrafine grain size and weak texture in an Mg-7Gd-5Y-1Nd-0.5Zr alloy. The results indicate that the structure of fine grain size and weak texture could be achieved after two cycles of multi-axial forging, which leads to a substantial mechanical properties improvement. The grain refinement mechanism and texture evolution of Mg-7Gd-5Y-1Nd-0.5Zr alloy during multi-axial forging have been investigated.

scholarly journals The Comparison in the Microstructure and Mechanical Properties between AZ91 Alloy and Nano-SiCp/AZ91 Composite Processed by Multi-Pass Forging Under Varying Passes and Temperatures

Materials ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 625 ◽  
Author(s):  
K.B. Nie ◽  
J.G. Han ◽  
K.K. Deng ◽  
X.J. Wang ◽  
C. Xu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Yield Strength ◽  
Grain Refinement ◽  
Texture Evolution ◽  
Az91 Alloy ◽  
Strengthening Effect ◽  
Sic Nanoparticles ◽  
Microstructure And Mechanical Properties ◽  
Second Phases

In this study, both AZ91 alloy and nano-SiCp/AZ91 composite were subjected to multi-pass forging under varying passes and temperatures. The microstructure and mechanical properties of the alloy were compared with its composite. After six passes of multi-pass forging at a constant temperature of 400 ℃, complete recrystallization occurred in both the AZ91 alloy and composite. The decrease of temperature and the increase of passes for the multi-pass forging led to further refinement of dynamic recrystallized grains and dynamic precipitation of second phases. The grain size of the nano-SiCp/AZ91 composite was smaller than that of the AZ91 alloy under the same multi-pass forging condition, which indicated that the addition of SiC nanoparticles were beneficial to grain refinement by pinning the grain boundaries. The texture intensity for the 12 passes of multi-pass forging with varying temperatures was increased compared with that after nine passes. The ultimate tensile strength is slightly decreased while the yield strength was increased unobviously for the AZ91 alloy with the decrease of temperature and the increase of the passes for the multi-pass forging. Under the same condition of multi-pass forging, the yield strength of the composite was higher than that of the AZ91 alloy due to the Orowan strengthening effect and grain refinement strengthening resulting from externally applied SiC nanoparticles and internally precipitated second phases. By comparing the microstructure and mechanical properties between the AZ91 alloy and nano-SiCp/AZ91 composite, the strength-toughness properties of the composites at room temperature were affected by the matrix grain size, texture evolution, SiC nanoparticles distribution and the precipitated second phases.

Microstructure and Mechanical Properties of an AZ31 Magnesium Alloy Processed by Accumulative Back Extrusion (ABE)

2010 ◽  
Vol 667-669 ◽  
pp. 1033-1038 ◽  
Author(s):  
Mahmood Fatemi Varzaneh ◽  
Jose María Cabrera ◽  
Abbas Zarei Hanzaki
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Grain Size ◽  
Az31 Alloy ◽  
Fine Grained ◽  
Fracture Elongation ◽  
Tension Tests ◽  
Az31 Mg Alloy ◽  
Average Grain Size ◽  
Scanning Electron

A new continuous severe plastic deformation (SPD) method called accumulative back extrusion (ABE) was employed to fabricate ultra-fine grained AZ31 Mg alloy. Microstructures of AZ31 alloy processed by ABE up to four passes at a temperature of 230 °C were investigated using field emission scanning electron microscopy (FESEM). The results showed that the initial average grain size of 25 µm was reduced to about 1 µm. It was also found out that the more passes gave more homogenous microstructure. In addition, in order to find the effect of grain size on the mechanical properties, micro-tension tests were carried out and the changes in the yield and tensile strength and fracture elongation were analyzed. The obtained tensile properties were discussed relying on the characteristics of as-processed microstructures.

Effect of Composite Master Alloy on Mechanical Properties and Electrochemical Corrosion of ZL101 Alloy

2013 ◽  
Vol 749 ◽  
pp. 407-413
Author(s):  
Hong Xu ◽  
Xin Zhang ◽  
Ji Ping Ren ◽  
Min Peng ◽  
Shi Yang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Tensile Strength ◽  
Grain Refinement ◽  
Master Alloy ◽  
Mass Fraction ◽  
Electrochemical Corrosion ◽  
Corrosion Performance ◽  
Obvious Effect ◽  
Mechanical Properties And Corrosion

The mechanical properties and corrosion performances of the ZL101 alloy modified by the composite master alloy were investigated. The results showed that the master alloy had not only obvious effect of grain refinement, but also a significant role in refining dendrite grain of ZL101 alloy. The grain size decreased dramatically from 150μm to 62μm when the addition of composite master alloy is up to 0.5%(mass fraction) and the temperature is 720 for 30 minutes,. Its tensile strength and elongation increased by 27% and 42% respectively. The grain refinement of ZL101 alloy decreased its corrosion performance. The morphology of Si changed into globular from needle modified by NaF, instead of AlTiB.

scholarly journals Investigation on the Microstructure of ECAP-Processed Iron-Aluminium Alloys

Materials ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 219
Author(s):  
Bernd-Arno Behrens ◽  
Kai Brunotte ◽  
Tom Petersen ◽  
Roman Relge
Keyword(s):  
Grain Refinement ◽  
Aluminium Alloys ◽  
Aluminium Content ◽  
Microstructure Development ◽  
Chamber Furnace ◽  
Fine Grained ◽  
Angular Pressing ◽  
Ecap Process ◽  
Average Grain Size ◽  
Forming Temperature

The present work deals with adjusting a fine-grained microstructure in iron-rich iron-aluminium alloys using the ECAP-process (Equal Channel Angular Pressing). Due to the limited formability of Fe-Al alloys with increased aluminium content, high forming temperatures and low forming speeds are required. Therefore, tool temperatures above 1100 °C are permanently needed to prevent cooling of the work pieces, which makes the design of the ECAP-process challenging. For the investigation, the Fe-Al work pieces were heated to the respective hot forming temperature in a chamber furnace and then formed in the ECAP tool at a constant punch speed of 5 mm/s. Besides the chemical composition (Fe9Al, Fe28Al and Fe38Al (at.%—Al)), the influences of a subsequent heat treatment and the holding time on the microstructure development were investigated. For this purpose, the average grain size of the microstructure was measured using the AGI (Average Grain Intercept) method and correlated with the aforementioned parameters. The results show that no significant grain refinement could be achieved with the parameters used, which is largely due to the high forming temperature significantly promoting grain growth. The holding times in the examined area do not have any influence on the grain refinement.

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