Mechanically programmed shape change in laminated elastomeric composites

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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Creep and Material Design

Material Science Research India ◽

10.13005/msri/090125 ◽

2012 ◽

Vol 9 (1) ◽

pp. 169-171

Author(s):

Ram Oruganti

Keyword(s):

High Temperature ◽

Creep Resistance ◽

Room Temperature ◽

Shape Change ◽

Creep Damage ◽

Material Design ◽

The Other ◽

Permanent Shape ◽

Total Life

When a material is subjected to temperature and stress, it deforms slowly resulting in permanent shape change. If the same amount of stress were applied at room temperature, the material would not budge. This deformation at high temperature under low stresses is called creep. This phenomenon is important for OEM’S like GE etc. since turbine components are exposed to low stress and high temperature and the resulting shape change is not a desirable consequence. Apart from the change in shape, the components can eventually rupture leading to catastrophic consequences. So it is imperative that the nature of this phenomenon is understood well. Some of the questions to be answered are 1) What makes one material more resistant to creep that the other 2) How can a material’s creep resistance be improved 3) How can the current creep damage in a component be measured 4) Is it possible to say what fraction of the total life of a component has been consumed by creep.

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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

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2013.03.008 ◽

2013 ◽

Vol 566 ◽

pp. 98-107 ◽

Cited By ~ 54

Author(s):

H. Yan ◽

S.W. Xu ◽

R.S. Chen ◽

S. Kamado ◽

T. Honma ◽

...

Keyword(s):

Room Temperature ◽

Tensile Deformation ◽

Rolled Sheet ◽

Basal Texture

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The room temperature tensile deformation behavior of thermomechanically processed β-metastable Ti-Nb-Ta-Zr bio-alloy: the role of deformation-induced martensite

Materials Science and Engineering A ◽

10.1016/j.msea.2018.09.038 ◽

2018 ◽

Vol 738 ◽

pp. 15-23 ◽

Cited By ~ 9

Author(s):

A. Maghsoudlou ◽

A. Zarei-Hanzaki ◽

H.R. Abedi ◽

A. Barabi ◽

F. Pilehva ◽

...

Keyword(s):

Deformation Behavior ◽

Room Temperature ◽

Tensile Deformation ◽

Tensile Deformation Behavior

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

Journal of Applied Mechanics ◽

10.1115/1.4039814 ◽

2018 ◽

Vol 85 (6) ◽

Cited By ~ 5

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.

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

MRS Proceedings ◽

10.1557/proc-753-bb5.19 ◽

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.

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Nano Effects of Helium Plasma Treatment Carbon Nanotubes Coating Basalt Filament

Materials Science Forum ◽

10.4028/www.scientific.net/msf.610-613.722 ◽

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.

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

Tribologia ◽

10.5604/01.3001.0010.5992 ◽

2017 ◽

pp. 39-45 ◽

Cited By ~ 2

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.

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