Tensile Deformation Behaviors of Ultrafine Grained Al-Fe-Si Alloy Sheets

Ultra-fine grained AA8011 alloy sheets manufactured by the accumulative roll-bonding (ARB) process exhibited unique tensile deformation behavior. Tensile strength of the ARB processed AA8011 sheets increased up to three cycles, but then showed nearly the same value after three cycles. Meanwhile, the total elongation grew significantly with an increasing nember of ARB cycles. It was found that the strain-rate sensitivities (m) of the AA8011 sheets increased up to 0.047 by the ARB process. A large number of high-angle boundaries were introduced by the ARB process and the fraction of high-angle boundaries reached 70% after eight ARB cycles. In this paper, we discusse the increase in total elongation on the basis of strain-rate sensitive deformation of the material, which is also correlated with dynamic recovery.

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The effect of strain rates on tensile deformation of ultrafine-grained copper

International Journal of Modern Physics B ◽

10.1142/s0217979217440143 ◽

2017 ◽

Vol 31 (16-19) ◽

pp. 1744014

Author(s):

M. Li ◽

Q. W. Jiang

Keyword(s):

Strain Rate ◽

Deformation Behavior ◽

Room Temperature ◽

Tensile Deformation ◽

Strain Rates ◽

Roll Bonding ◽

Fracture Elongation ◽

Tensile Deformation Behavior ◽

Ultrafine Grained ◽

Flow Stress Level

Tensile deformation behavior of ultrafine-grained (UFG) copper processed by accumulative roll-bonding (ARB) was studied under different strain rates at room temperature. It was found that the UFG copper under the strain rate of 10[Formula: see text] s[Formula: see text] led to a higher strength (higher flow stress level), flow stability (higher stress hardening rate) and fracture elongation. In the fracture surface of the sample appeared a large number of cleavage steps under the strain rate of 10[Formula: see text] s[Formula: see text], indicating a typical brittle fracture mode. When the strain rate is 10[Formula: see text] or 10[Formula: see text] s[Formula: see text], a great amount of dimples with few cleavage steps were observed, showing a transition from brittle to plastic deformation with increasing strain rate.

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Strain Rate Contribution due to Dynamic Recovery of Ultrafine-Grained Cu–Zr as Evidenced by Load Reductions during Quasi-Stationary Deformation at 0.5 Tm

Metals ◽

10.3390/met9111150 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1150 ◽

Cited By ~ 2

Author(s):

Wolfgang Blum ◽

Jiři Dvořák ◽

Petr Král ◽

Philip Eisenlohr ◽

Vaclav Sklenička

Keyword(s):

Strain Rate ◽

Dynamic Recovery ◽

Tensile Deformation ◽

Coarse Grained ◽

Internal Stresses ◽

Back Flow ◽

Stationary Rate ◽

Ultrafine Grained ◽

High Fraction ◽

And Storage

During quasi-stationary tensile deformation of ultrafine-grained Cu-0.2 mass%Zr at 673 K and a deformation rate of about e - 4 / s load changes were performed. Reductions of relative load by more than about 25% initiate anelastic back flow. Subsequently, the creep rate turns positive again and goes through a relative maximum. This is interpreted by a strain rate component ϵ ˙ - associated with dynamic recovery of dislocations. Back extrapolation indicates that ϵ ˙ - contributes the same fraction of ( 20 ± 10 ) % to the quasi-stationary strain rate that has been reported for coarse-grained materials with high fraction of low-angle boundaries; this suggests that dynamic recovery of dislocations is generally mediated by boundaries. The influence of anelastic back flow on ϵ ˙ - is discussed. Comparison of ϵ ˙ - to the quasi-stationary rate points to enhancement of dynamic recovery by internal stresses. Subtraction of ϵ ˙ - from the total rate yields the rate component ϵ ˙ + related with generation and storage of dislocations; its activation volume is in the order expected from the classical theory of thermal glide.

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Tensile Deformation Behavior at High Strain Rate for Ultrafine-grained Ferrite cementite Steels

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.90.12_1043 ◽

2004 ◽

Vol 90 (12) ◽

pp. 1043-1049 ◽

Cited By ~ 14

Author(s):

Noriyuki TSUCHIDA ◽

Yo TOMOTA ◽

Kotobu NAGAI

Keyword(s):

High Strain Rate ◽

Strain Rate ◽

Deformation Behavior ◽

High Strain ◽

Tensile Deformation ◽

Tensile Deformation Behavior ◽

Ultrafine Grained

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Martensitic Transformation from Ultrafine Grained Austenite Fabricated by ARB in Fe-24Ni-0.3C

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.361 ◽

2010 ◽

Vol 667-669 ◽

pp. 361-366 ◽

Cited By ~ 4

Author(s):

Hamidreza Jafarian ◽

Ehsan Borhani ◽

Akinobu Shibata ◽

Daisuke Terada ◽

Nobuhiro Tsuji

Keyword(s):

Martensitic Transformation ◽

Accumulative Roll Bonding ◽

Martensite Transformation ◽

Early Stage ◽

Crystallographic Analysis ◽

High Angle ◽

Metastable Austenite ◽

Roll Bonding ◽

Nucleation Sites ◽

Ultrafine Grained

In this paper, martensitic transformation from ultrafine grained (UFG) austenite fabricated by accumulative roll bonding (ARB) process in a metastable austenite alloy was studied. Microstructural observations and crystallographic analysis were carried out by FE-SEM/EBSD. The results showed that elongated UFG austenite having 200-300 nm in thickness surrounded by high angle boundaries was obtained after 6 cycles of the ARB process. The martensite transformed from the UFG austenite showed characteristic morphology and texture. The martensite transformation starting (Ms) temperature increased after 1 cycle ARB, which is related to increasing amount of nucleation sites, such as low angle boundaries, introduced during early stage of ARB process. In contrast, by increasing the ARB cycles, Ms temperature decreased. Decreasing the Ms temperature could be correlated to strengthening of austenite by the ARB process.

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Effects of temperature and strain rate on tensile deformation behavior of superalloy UNS N10276

Materials Science and Engineering A ◽

10.1016/j.msea.2017.05.085 ◽

2017 ◽

Vol 699 ◽

pp. 88-98 ◽

Cited By ~ 11

Author(s):

Enxiang Pu ◽

Wenjie Zheng ◽

Zhigang Song ◽

Han Feng ◽

Feng Yang ◽

...

Keyword(s):

Strain Rate ◽

Deformation Behavior ◽

Tensile Deformation ◽

Tensile Deformation Behavior ◽

Effects Of Temperature

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Tensile Deformation Behavior of 5A90 Al-Li Alloy Sheet at Elevated Temperature

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.66-68.70 ◽

2011 ◽

Vol 66-68 ◽

pp. 70-75 ◽

Cited By ~ 1

Author(s):

Gao Shan Ma ◽

Song Yang Zhang ◽

Han Ying Wang ◽

Min Wan

Keyword(s):

Flow Stress ◽

Strain Rate ◽

Deformation Behavior ◽

Tensile Deformation ◽

Alloy Sheet ◽

Hot Forming ◽

Uniaxial Tensile ◽

Sensitivity Index ◽

Tensile Deformation Behavior ◽

Increasing Temperature

Uniaxial tensile deformation behavior of 5A90 aluminium-lithium alloy sheet is investigated in the hot forming with the temperature range of 200-450°C and strain rate range of 0.3×10-3-0.2×10-1s-1. It is found that the flow stress of 5A90 Al-Li alloy in uniaxial tension increase with increasing strain rate and decrease with increasing temperature, however, the tendency of total elongation is just the reverse, and the optimum forming temperature is 400°C. The strain rate sensitivity index (m-value) remarkably increases with increasing temperature for a given strain rate. It is shown that 5A90 Al-Li alloy sheet displays the sensitivity to the strain rate at elevated temperatures. For a given strain rate, the strain hardening index (n-value) decreases with increasing temperature, whereas the n-value increases above 350°C. The constitutive equation of stress, strain and strain rate for 5A90 Al-Li alloy at any temperature is obtained by fitting the experimental data, which gave a good flow stress model for the FEM simulation of hot forming.

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Effects of Gage Diameter and Strain Rate on Tensile Deformation Behavior of 32Mn-7Cr Steel at 4 K

Advances in Cryogenic Engineering Materials ◽

10.1007/978-1-4613-9871-4_37 ◽

1986 ◽

pp. 313-320 ◽

Cited By ~ 5

Author(s):

Kotobu Nagai ◽

Tetsumi Yuri ◽

Yuji Nakasone ◽

Toshio Ogata ◽

Keisuke Ishikawa

Keyword(s):

Strain Rate ◽

Deformation Behavior ◽

Tensile Deformation ◽

Tensile Deformation Behavior

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Mechanical Properties of an Accumulative Roll Bonded Aluminium Alloy Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.618-619.551 ◽

2009 ◽

Vol 618-619 ◽

pp. 551-554 ◽

Cited By ~ 2

Author(s):

O. Al-Buhamad ◽

M. Zakaria Quadir ◽

Michael Ferry

Keyword(s):

Mechanical Properties ◽

Grain Boundaries ◽

Annealing Temperature ◽

Sheet Material ◽

Commercial Purity ◽

Alloy Composite ◽

High Angle ◽

Roll Bonding ◽

Fine Grained ◽

Strength And Ductility

A multilayered sheet composite of commercial purity Al and Al-0.3%Sc alloys was produced by accumulative roll bonding. The final sheet material consisted of 64 ultra fine grained layers, each of ~7.8mm in thickness. The as-deformed material was annealed at temperatures ranging from 250 to 350°C to study the changes in microstructure and their associated influence on mechanical properties. The as-deformed structures largely comprised of high angle grain boundaries in the Al layers and low angle grain boundaries in the Al(Sc) layers. During annealing, the structures in the Al(Sc) layers remained unaltered, whereas the Al layers recrystallized rapidly to the full layer thickness. The mechanical properties of the Al-Al(Sc) composite were measured and found to be unique in strength and ductility with annealing temperature having a significant influence on these properties.

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