Activation of {102} twinning and slip in high ductile Mg–2.0Zn–0.8Gd rolled sheet with non-basal texture during tensile deformation at room temperature

2013 ◽  
Vol 566 ◽  
pp. 98-107 ◽  
Author(s):  
H. Yan ◽  
S.W. Xu ◽  
R.S. Chen ◽  
S. Kamado ◽  
T. Honma ◽  
...  
Keyword(s):  
Room Temperature ◽  
Tensile Deformation ◽  
Rolled Sheet ◽  
Basal Texture

Influences of Tensile Temperature on the Mechanical Properties of Rolled Mg-Zn-Gd Sheets with Non-Basal Texture

2015 ◽  
Vol 816 ◽  
pp. 381-386
Author(s):  
H. Yan ◽  
R.S. Chen ◽  
E.H. Han
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Tensile Deformation ◽  
Rolling Direction ◽  
Tensile Tests ◽  
Rolling Process ◽  
Basal Texture ◽  
Forming Process ◽  
Microstructure Observation ◽  
Increasing Temperature

Mg-2.0Zn-xGd sheets with non-basal texture were fabricated by common rolling process, which showed excellent ductility and formability at room temperature. In this paper, tensile tests were carried out at moderate temperature along the rolling direction and transverse direction to evaluate the influences of tensile temperature on mechanical properties and formability of the sheet. The microstructural evolution during tensile deformation was also investigated to analysis deformation mechanisms. The results showed that the elongation of the sheets increased from 57% at 373K to 253% at 573°C along the rolling direction, while the yield strength decreased with the increase of tensile temperature. The microstructure observation indicated that twining was one of the deformation modes and no dynamic recrytallization took place during deformation at 373K. With temperature increasing up to 473K, dynamic recrystallization took place and led to finer microstructure. This suggests that the formability of the Mg-Zn-Gd sheets with high ductility at room temperature could be further improved by increasing temperature up to 473K, which could refine the microstructure leading to higher strength during second forming process.

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

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.

Texture of AZ31 Magnesium Alloy Sheet Heavily Rolled by High Speed Warm Rolling

2007 ◽  
Vol 539-543 ◽  
pp. 3359-3364 ◽  
Author(s):  
Tetsuo Sakai ◽  
Hiroshi Utsunomiya ◽  
H. Koh ◽  
S. Minamiguchi
Keyword(s):  
Magnesium Alloy ◽  
High Speed ◽  
Room Temperature ◽  
Alloy Sheet ◽  
Rolling Temperature ◽  
Az31 Magnesium Alloy ◽  
Basal Texture ◽  
Double Peak ◽  
Magnesium Alloy Sheet ◽  
Az31 Magnesium Alloy Sheet

Magnesium alloy sheets had to be rolled at elevated temperature to avoid cracking. The poor workability of magnesium alloy is ascribed to its hcp crystallography and insufficient activation of independent slip systems. Present authors have succeeded in 1-pass heavy rolling of AZ31 magnesium alloy sheet below 473K by raising rolling speed above 1000m/min. Heavy reduction larger than 60% can be applied by 1-pass high speed rolling even at room temperature. The improvement of workability at lower rolling temperature is due to temperature rise by plastic working. The texture of heavily rolled AZ31 magnesium alloy sheet is investigated in the present study. The texture of sheets rolled 60% at room temperature was <0001>//ND basal texture. At the rolling temperature above 373K, the peak of (0001) pole tilted ±10-15 deg toward RD direction around TD axisto form a double peak texture. The texture varied through thickness. At the surface, the (0001) peak tilted ±10-15 deg toward TD direction around RD axis to form a TD-split double peak texture. The direction of (0001) peak splitting rotated 90 deg from the surface to the center of thickness. Heavily rolled magnesium alloy sheets have non-basal texture. The sheets having non-basal texture are expected to show better ductility than sheets with basal texture.

Uniaxial Ratchetting of Filled Rubber: Experiments and Damage-Coupled Hyper-Viscoelastic-Plastic Constitutive Model

2018 ◽  
Vol 85 (6) ◽  
Author(s):  
Yifu Chen ◽  
Guozheng Kang ◽  
Jianghong Yuan ◽  
Chao Yu
Keyword(s):  
Experimental Data ◽  
Constitutive Model ◽  
Applied Stress ◽  
Stress Level ◽  
Cyclic Deformation ◽  
Room Temperature ◽  
Tensile Deformation ◽  
Accumulated Damage ◽  
Filled Rubber ◽  
Cyclic Tension

A series of stress-controlled uniaxial cyclic tension-unloading tests are discussed to investigate the ratchetting of a filled rubber at room temperature. It is shown that obvious ratchetting occurs and depends apparently on the applied stress level, stress rate, and stress history. Based on the experimental observations, a damage-coupled hyper-viscoelastic-plastic constitutive model is then developed to describe the ratchetting of the filled rubber, which consists of three branches in parallel, i.e., a hyperelastic, a viscoelastic, and a plastic one. The damage is assumed to act equally on three branches and consists of two parts, i.e., the Mullins-type damage caused by the initial tensile deformation and the accumulated damage occurred during the cyclic deformation. The developed model is validated by comparing the predicted results with the experimental data.

Effect of Interphase Boundary Character on Mechanical Properties in NiAl(β) Bicrystals with Ni 3Al(γ') Precipitates along Grain Boundary

2002 ◽  
Vol 753 ◽  
Author(s):  
Toshiya Sakata ◽  
Hiroyuki Y. Yasuda ◽  
Yukichi Umakoshi
Keyword(s):  
Mechanical Properties ◽  
Interphase Boundary ◽  
Fracture Stress ◽  
Room Temperature ◽  
Tensile Deformation ◽  
Deviation Angle ◽  
Boundary Character ◽  
Temperature Fracture ◽  
Boundary Sliding

ABSTRACTRole of the crystallography of Ni 3Al(γ') precipitates along grain boundaries of NiAl(β) in the mechanical properties was systematically investigated using β bicrystals with controlled orientations. γ' phase preferentially precipitated along βgrain boundaries showing a film-like shape. The selected variant of γ'-film satisfied the Kurdjumov-Sachs (K-S) relation with a neighboring βcrystal but it deviated from the relation with another adjacent βcrystal. In the course of tensile deformation at room temperature, fracture occurred preferentially at incoherent (β/γ') interphase boundary deviating from the K-S relation and the fracture stress decreased with increasing deviation angle. In contrast, the interphase boundary sliding occurred preferentially at irrational (β/γ') interface at 1073K. The sliding displacement increased with increasing deviation angle. Thus, the mechanical properties of β bicrystals with γ'-film were found to depend strongly on the interphase boundary character.

scholarly journals Influence of Wavy Bending on Microstructure and Mechanical Properties of a Rolled AZ31 Sheet

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 173 ◽  
Author(s):  
Tingting Liu ◽  
Yuyang Zhang ◽  
Yanan Chen ◽  
Zhiwen Du ◽  
Hongbing Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Tensile Ductility ◽  
Recrystallization Annealing ◽  
Basal Texture ◽  
Grain Coarsening ◽  
Microstructure And Mechanical Properties ◽  
Combined Use ◽  
Az31 Sheet ◽  
Stretch Formability

In the present work, cross-wavy bending at room temperature was carried out to tailor the microstructure and stretch formability of rolled AZ31 sheets. Wavy bending processing generates profuse {10–12} twins and a tilt basal texture. Subsequent recrystallization annealing causes grain coarsening and enhances the intensity of twin-orientation. The combined use of wavy bending and annealing can maintain high tensile ductility and remarkably enhances the stretch formability of rolled AZ31 sheet. It can be mainly attributed to the non-basal texture in the wavy bent sheet which increases the thinning capability during in-plane tension.

Nano Effects of Helium Plasma Treatment Carbon Nanotubes Coating Basalt Filament

2009 ◽  
Vol 610-613 ◽  
pp. 722-727
Author(s):  
J.N. Huang ◽  
Ying Chen Zhang ◽  
H.Y. Wu ◽  
Y.P. Qiu
Keyword(s):  
Carbon Nanotube ◽  
Plasma Treatment ◽  
Room Temperature ◽  
Tensile Deformation ◽  
Basalt Fiber ◽  
Fiber Surface ◽  
Contact Angles ◽  
Structural Parameter ◽  
Oxygen Plasma Treatment ◽  
Helium Plasma

The plasticity of APPJ treatment on microstructure and tensile deformation of carbon nanotube coating basalt fiber in the dynamic states was investigated by specialized tensile testing at room temperature. With the addition of low-temperature helium plasma treatment, Young's modulus and yield stress changed. It was found that micro-structural parameter such as the activation volume was important descriptors for carbon nanotube coating basalt fiber and inter-phase effect on strength. The different APPJ treatments on the carbon nanotube coating basalt fiber showed the change rate sensitivity. Results revealed that APPJ treatment carbon nanotube coating basalt fiber and the inter-phase would enhance the ductility of basalt at room temperature. From the SEM micrographs, an increase in surface roughness has been observed and the degree of fibrillation decreased after helium and oxygen plasma treatment. Contact angle analysis showed taht the treated Basalt filament had lower contact angles than the untreated one. Based on FTIR results, the change of wettability and surface energy depended the amount of polar functional groups on the fiber surface introduced by the treatments.

Rolling Temperature and Subsequent Annealing on Microstructure, Texture and Mechanical Properties of Consecutive Rolled Mg-2.0Zn-0.8Gd Alloy

2013 ◽  
Vol 747-748 ◽  
pp. 369-376 ◽  
Author(s):  
Hong Yan ◽  
Rong Shi Chen ◽  
En Hou Han
Keyword(s):  
Mechanical Properties ◽  
Dynamic Recrystallization ◽  
Transverse Direction ◽  
Rolling Direction ◽  
Annealing Process ◽  
Normal Direction ◽  
Rolling Temperature ◽  
Rolled Sheet ◽  
Basal Texture ◽  
Different Temperatures

Mg-2.0Zn-0.8Gd (wt. %) alloy was rolled consecutively at different temperatures. The influence of rolling temperature and annealing process on the microstructure, texture and mechanical properties of the sheet were investigated. A deformation microstructure consisting of many intersected twins and a few dynamic recrystallization grains, and a basal texture with basal poles tilting about ± 10-15° from the normal direction towards the rolling direction were observed in the as-rolled sheet after 4 consecutive rolling processes. Static recrystallizaiton took place in the sheet after annealed above 300 °C. The annealed sheet exhibited a uniform microstructure and a non-basal texture with basal poles tilting about ± 38-43° from the normal direction towards the transverse direction. The annealed sheets exhibited higher ductility about 32% along the rolling direction and 40% along the transverse direction comparing with the as-rolled sheets. The static recrystallization during annealing process was helpful to modify the texture as well as the dynamic recrystallization during rolling in the RE-containing alloys.

THE INFLUENCE OF A CONSTANT STATE OF DEFORMATION ON THE FRICTION COEFFICIENT IN SELECTED THERMOPLASTICS (POLYMER–STEEL PAIR)

Tribologia ◽  
2017 ◽  
pp. 39-45 ◽  
Author(s):  
Maciej KUJAWA ◽  
Wojciech WIELEBA
Keyword(s):  
Room Temperature ◽  
Tensile Deformation ◽  
Small Deformation ◽  
Static Friction ◽  
Kinetic Friction ◽  
High Deformation ◽  
Polymer Properties ◽  
The Coefficient Of Friction ◽  
Constant State ◽  
Friction Polymer

The effect of tensile deformation on polymer structures and their mechanical properties is described in various papers. However, the majority of articles are focused on high deformation (a few hundred percentiles) at increased temperature. It causes changes in orientation and the crystallinity ratio. The authors of this paper asses the influence of strain (max. 50%) on hardness and the coefficient of friction (polymer–steel A1 couple) for selected polymers. The deformation was conducted at room temperature and maintained during tests. There was a significant reduction (up to 50%) of hardness after deformation, in the case of all examined polymers. In the case of PE-HD, the coefficient of kinetic friction almost doubled its value (89% increase). The reduction of the coefficient of static friction for sliding pairs that include PTFE and PA6 was about 26% (in comparison with non-deformed polymer). For all investigated polymers, hardness increased over time (up to 40% after 24 hours). Coefficients of static and kinetic friction decreased in 24 hours (up to 29% coefficient of static friction and 19% coefficient of kinetic friction). The research shows that a small deformation causes changes in polymer properties. Moreover, these changes appear at room temperature directly after deformation.

Sign in / Sign up

Export Citation Format

Share Document