Characterization of Plastic Anisotropy of AA5182-O Sheets During Prestraining and Subsequent Annealing

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Kaifeng Wang ◽  
Bonan Zhou ◽  
Jingjing Li ◽  
John E. Carsley ◽  
Yang Li
Keyword(s):  
Electron Backscatter Diffraction ◽  
Plastic Anisotropy ◽  
Rolling Direction ◽  
Anisotropy Coefficient ◽  
Normal Anisotropy ◽  
Aluminum Alloy 5182 ◽  
Annealing Conditions ◽  
R Value ◽  
Value Changes ◽  
Backscatter Diffraction

This paper described the effects of prestraining and annealing on plastic anisotropy (r-value) of aluminum alloy 5182-O sheets including two prestrain paths and two annealing conditions. During the prestraining and annealing processes, r-value changed depending on prestrain paths and annealing conditions. Although there were slight changes of the normal anisotropy coefficient, r¯, during prestraining and annealing processes, the planar anisotropy coefficient, Δr, increased significantly, especially for the uniaxial prestrain condition. This could accelerate the development of earing during a sheet forming operation. Also, the corresponding sheet textures in rolling direction (RD)/TD plane after prestraining and annealing processes were observed through electron backscatter diffraction (EBSD) analysis to explain the r-value changes, where the viscoplastic self-consistent (VPSC) model was used to correlate the determined texture to measured r-values. It is found that the sheet texture also had significant changes relating to the prestrain paths and annealing conditions resulting in varied r-values.

scholarly journals Influence of Continuous Annealing Temperature on Mechanical Properties and Texture of Battery Shell Steel

Metals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 52 ◽  
Author(s):  
Beijia Ning ◽  
Zhengzhi Zhao ◽  
Zhiying Mo ◽  
Hong Wu ◽  
Chong Peng ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Annealing Temperature ◽  
Electron Backscatter Diffraction ◽  
Continuous Annealing ◽  
Normal Anisotropy ◽  
Fracture Elongation ◽  
Anisotropy Index ◽  
R Value ◽  
Backscatter Diffraction ◽  
Annealing Experiments

To study the influences of continuous annealing temperature on microstructure, mechanical properties and textures of battery shell steel, continuous annealing experiments were conducted at 710 °C, 730 °C, 760 °C and 780 °C respectively. The mechanical properties and normal anisotropy index (r) were measured by tensile test and the textures were investigated using the method of electron backscatter diffraction (EBSD). The results show that as annealing temperature rose, the grain size, fracture elongation and r value increased, whereas the strength and yield ratio decreased. The yield strength was 122 MPa, the tensile strength was 286 MPa, meanwhile the elongation and r value arrived at 38.8% and 2.3 when the annealing temperature rose to 780 °C. After annealing, the main texture in battery shell steel is {111} <112>, followed by {111} <110>. With the increase of annealing temperature, textures in {001} crystallographic plane weakened while textures in {111} plane strengthened, which is beneficial to the deep drawability of the steel.

Effect of Strain on the Anisotropy Coefficient of Sheet Alloys AA2024, Ti-2Al-1Mn, Titanium Grade 2, STEEL X10CrNiTi18-9

2016 ◽  
Vol 684 ◽  
pp. 366-370 ◽  
Author(s):  
Ekaterina A. Nosova ◽  
Fedor Vasilievich Grechnikov
Keyword(s):  
Titanium Alloys ◽  
Rolling Direction ◽  
Anisotropy Coefficient ◽  
Transverse Deformation ◽  
Plastic Properties ◽  
Uniaxial Test ◽  
R Value ◽  
Titanium Grade ◽  
Deformation Coefficient ◽  
Anisotropy Coefficients

Anisotropy of the plastic properties is an index of sheet’s ability to stamping. In this work the transverse deformation coefficient and r-value were used. Uniaxial test was made for annealed pieces of 1 mm thickness from aluminum alloy AA2024, steel X10CrNiTi18-9, Titanium Grade 2 and titanium alloy Ti-2Al-1Mn. Pieces were cut at angle of 0, 22.5, 45, 67.5 and 90O to the rolling direction. Steel pieces have anisotropy coefficients practically independent from angle between it’s’ axis and the rolling direction. Pieces made of AA2024 cut at angle 45О to the rolling direction have largest anisotropy coefficients. Titanium alloys have the largest coefficients for angle 67,5О between axis of piece and the rolling direction. Both indexes of anisotropy are higher for titanium alloys, which is property of HCP-metals.

Mesoscopic EBSD Analysis and Mesomechanical Behavior of Ridging or Roping in AA6XXX Alloys

2011 ◽  
Vol 702-703 ◽  
pp. 955-958 ◽  
Author(s):  
Ling Qin ◽  
Marc Seefeldt ◽  
Tricia A. Bennett ◽  
Roumen H. Petrov ◽  
Paul van Houtte
Keyword(s):  
Surface Roughness ◽  
Mechanical Response ◽  
Electron Backscatter Diffraction ◽  
Surface Roughening ◽  
Test Case ◽  
Present Contribution ◽  
Orientation Maps ◽  
Mesoscopic Level ◽  
R Value ◽  
Backscatter Diffraction

Aluminium alloys for car body manufacturing often show a specific type of band-shaped surface roughening upon stretching, called “ridging” or “roping”. Experimental research as well as modelling attempts have indicated that the evolving surface roughness profiles cannot be understood based on banding of individual surface texture components, like cube or Goss, only. Therefore, it is proposed to study banding on the “mesoscopic” level of texture banding rather than on the “microscopic” one of orientation banding. In mechanical terms, such patterning in the texture would lead to patterning in, for instance, the Lankford coefficient (r-value), so that the mechanical response can be calculated on an intermediate length scale. The present contribution presents a method for calculating r-value patterning from Electron Backscatter diffraction (EBSD) orientation maps. In a first test case of a strongly ridging AA6xxx sheet, indeed patterning in the r-value is found which corresponds to reported patterning of the surface roughness.

Microstructure and Microtexture Evolution of Invar Alloy after Cross Accumulative Roll Bonding (CARB) Compared to ARB

2016 ◽  
Vol 879 ◽  
pp. 744-749 ◽  
Author(s):  
Kamel Tirsatine ◽  
Hiba Azzeddine ◽  
Thierry Baudin ◽  
Anne Laure Helbert ◽  
Francois Brisset ◽  
...  
Keyword(s):  
Accumulative Roll Bonding ◽  
Volume Fraction ◽  
Electron Backscatter Diffraction ◽  
Rolling Direction ◽  
Grain Structure ◽  
Subgrain Structure ◽  
Roll Bonding ◽  
Ni Alloy ◽  
Backscatter Diffraction ◽  
Microstructure And Microtexture

The microstructure and microtexture evolution of a Fe-36%Ni alloy processed by cross accumulative roll-bonding was investigated using Electron BackScatter Diffraction. Deformation led to the development of elongated ultrafine grains parallel to the rolling direction that subsequently became more equiaxed. The grains were more effectivelly refined after CARB than after ARB processing. The grain aspect ratio (l/L) decreased (which means a trend towards elongated sub-grain structure) after 2 and 3 CARB processing cycles and then increased (which means a trend towards equiaxed subgrain structure) from 4 to 5 cycles. The fraction of HAGB, CSL boundaries and the estimated deformed volume fraction gradually increased with increasing number of CARB cycles. Copper-type texture was observed after CARB odd cycles (RD//RD), while after even cycles (RD//TD) a new texture component named H ({012}<221>) was observed.

Effect of Phosphorus on the Mechanical Properties and Microstructure of Interstitial Free Steel

2012 ◽  
Vol 217-219 ◽  
pp. 433-436
Author(s):  
Zhi Fen Wang ◽  
Rong Dong Han ◽  
Shun Bin Zhou ◽  
Hai E Huang ◽  
Li Xin Wu
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Electron Backscatter Diffraction ◽  
Recrystallization Process ◽  
Interstitial Free ◽  
If Steel ◽  
P Content ◽  
Average Grain Size ◽  
R Value ◽  
Backscatter Diffraction

Effect of phosphorus content on the mechanical properties and microstructure of IF steel sheets was investigated. Average grain size and recrystallization texture were measured by electron backscatter diffraction (EBSD). The results showed that the higher P resulted in higher tensile strength and lowered the elongation and r-value. The average grain size increased with decreasing P content. The //ND (γ-fiber) pole intensity had a lowest value for IF steel with the highest P content which in turn deteriorate r-value. The element P played an important role in recrystallization process which affected the mechanical properties and microstructure of IF steels.

scholarly journals Determination of the Forming Limit for a ZIRLO™ Sheet with High Anisotropy

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5743
Author(s):  
Minsoo Kim ◽  
Seokmoo Hong
Keyword(s):  
Effective Stress ◽  
Effective Strain ◽  
Tensile Tests ◽  
Image Correlation ◽  
Dome Height ◽  
Forming Limit ◽  
Stress And Strain ◽  
Anisotropy Coefficient ◽  
Normal Anisotropy ◽  
R Value

In this study, the experimental two-dimensional forming limit diagram (FLD) data for a ZIRLO™ sheet, which is used in nuclear fuel rod support grids, were converted and presented as a triaxiality failure diagram (TFD). Most previous studies assumed ZIRLO™ to be isotropic when calculating the effective stress and strain. However, for highly anisotropic materials, the anisotropy should be considered for calculations of effective stress and strain; hence, in this study, they were calculated by introducing the normal anisotropy coefficient. To obtain this parameter of the ZIRLO™ specimens, tensile tests were performed on specimens with 0°, 45°, and 90° angles with respect to the rolling direction. It was observed that the average normal anisotropy coefficient measured during the tests was 4.94, which is very high. The von Mises isotropic and Hill 48 anisotropic yield criterion were applied to the FLD data that were experimentally determined using a limit dome height test and were converted into effective stress and effective strain. When the FLD is converted to TFD, the curve will increase in the top-right direction if the r-value is greater than 1, and this become more severe as the r-value increases. The TFD, which was converted considering the anisotropy, is almost the same to the TFD obtained using the digital image correlation method in the tensile tests of four specimens with different stress states. If anisotropy is not considered, then the formability is normally underestimated. However, a highly accurate TFD can be obtained with the method proposed in this study.

Effects of Annealing Conditions on Recrystallization, Texture, and Average Normal Anisotropy Coefficient of a Niobium-Stabilized Ferritic Stainless Steel

2017 ◽  
Vol 88 (12) ◽  
pp. 1700214 ◽  
Author(s):  
Daniella Gomes Rodrigues ◽  
Cláudio Moreira de Alcântara ◽  
Dagoberto Brandão Santos ◽  
Tarcísio Reis de Oliveira ◽  
Berenice Mendonça Gonzalez
Keyword(s):  
Stainless Steel ◽  
Ferritic Stainless Steel ◽  
Recrystallization Texture ◽  
Anisotropy Coefficient ◽  
Normal Anisotropy ◽  
Annealing Conditions

scholarly journals Effect of annealing temperature and time on recrystallization behavior of Mg-Gd-Y-Zn-Zr alloy

2021 ◽  
Author(s):  
Rui Han ◽  
Leichen Jia ◽  
Zhimin Zhang ◽  
Qiang Wang ◽  
Jianmin Yu ◽  
...  
Keyword(s):  
Annealing Temperature ◽  
Electron Backscatter Diffraction ◽  
Extrusion Direction ◽  
Annealing Treatment ◽  
Optical Microscope ◽  
Abnormal Growth ◽  
Annealing Conditions ◽  
Grain Distribution ◽  
Backscatter Diffraction ◽  
Zr Alloy

Abstract In this paper, the effect of annealing treatment on the microstructure and hardness of extruded Mg-9Gd-4Y-2Zn-0.5Zr alloy (wt. %) was discussed. The microstructure evolution of the alloy under different annealing conditions was studied by optical microscope (OM), scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD), and the variation of hardness was analyzed. With the increase of annealing temperature, the large deformed grains first break into small recrystallized grains. When the temperature continues to increase, the recrystallized grains grow abnormally with the precipitation of chain phase and the fragmentation of lamellar long-period stacking ordered (LPSO) phase. The alloy does not recrystallize at low temperature, and the recrystallized grains grow abnormally at high temperature. The increase of annealing time will also lead to abnormal growth of recrystallized grains. The texture gradually diffuses from the classical extrusion texture to the extrusion direction (ED). The results show that under the condition of 430 °C × 5h, the recrystallization volume of the alloy is the largest, the recrystallization grain distribution is uniform, and the hardness value is the highest.

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