Uniaxial deformation of partially crystalline oriented polymers (fibers)

1970 ◽  
Vol 3 (1) ◽  
pp. 14-16
Author(s):  
V. E. Zgaevskii
Keyword(s):  
Uniaxial Deformation ◽  
Oriented Polymers

Comparison of Substructures Between Uniaxial and Biaxial Deformation in 1100-0 Aluminum

1981 ◽  
Vol 39 ◽  
pp. 52-53
Author(s):  
D. L. Rohr ◽  
S. S. Hecker
Keyword(s):  
Plastic Strain ◽  
Cell Walls ◽  
Room Temperature ◽  
Mechanical Response ◽  
Biaxial Tension ◽  
Initial Deformation ◽  
Uniaxial Deformation ◽  
Biaxial Deformation ◽  
Stress States ◽  
Comprehensive Study

As part of a comprehensive study of microstructural and mechanical response of metals to uniaxial and biaxial deformations, the development of substructure in 1100 A1 has been studied over a range of plastic strain for two stress states.Specimens of 1100 aluminum annealed at 350 C were tested in uniaxial (UT) and balanced biaxial tension (BBT) at room temperature to different strain levels. The biaxial specimens were produced by the in-plane punch stretching technique. Areas of known strain levels were prepared for TEM by lapping followed by jet electropolishing. All specimens were examined in a JEOL 200B run at 150 and 200 kV within 24 to 36 hours after testing.The development of the substructure with deformation is shown in Fig. 1 for both stress states. Initial deformation produces dislocation tangles, which form cell walls by 10% uniaxial deformation, and start to recover to form subgrains by 25%. The results of several hundred measurements of cell/subgrain sizes by a linear intercept technique are presented in Table I.

scholarly journals Effect of Deformation on Topological Properties of Cobalt Monosilicide

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 143
Author(s):  
Sergey Nikolaev ◽  
Dmitry Pshenay-Severin ◽  
Yuri Ivanov ◽  
Alexander Burkov
Keyword(s):  
Band Structure ◽  
Ab Initio Calculations ◽  
Topological Charge ◽  
External Stress ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Topological Properties ◽  
Uniaxial Deformation ◽  
Band Crossing ◽  
Topological Charges

Recently, it was shown that materials with certain crystal structures can exhibit multifold band crossings with large topological charges. CoSi is one such material that belongs to non-centrosymmetric space group P213 (#198) and posseses multifold band crossing points with a topological charge of 4. The change of crystal symmetry, e.g., by means of external stress, can lift the degeneracy and change its topological properties. In the present work, the influence of uniaxial deformation on the band structure and topological properties of CoSi is investigated on the base of ab initio calculations. The k·p Hamiltonian taking into account deformation is constructed on the base of symmetry consideration near the Γ and R points both with and without spin-orbit coupling. The transformation of multifold band crossings into nodes of other types with different topological charges, their shift both in energy and in reciprocal space and the tilt of dispersion around nodes are studied in detail depending on the direction of uniaxial deformation.

scholarly journals Effect of tungsten disulfide nanotubes on crystallization of polylactide under uniaxial deformation and annealing

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Fausta Loffredo ◽  
Loredana Tammaro ◽  
Tiziana Di Luccio ◽  
Carmela Borriello ◽  
Fulvia Villani ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Structural Evolution ◽  
Tungsten Disulfide ◽  
Fine Tuning ◽  
Nanocomposite Films ◽  
Uniaxial Deformation ◽  
Scanning Calorimetry ◽  
X Ray ◽  
X Ray Scattering

AbstractTungsten disulfide (WS2) nanotubes (NTs) are examined here as a filler for polylactide (PLA) for their ability to accelerate PLA crystallization and for their promising biocompatibility in relevant to biomedical applications of PLA-WS2 nanocomposites. In this work, we have studied the structural and thermal properties of PLA-WS2 nanocomposite films varying the concentration of WS2 NTs from 0 (neat PLA) to 0.6 wt%. The films were uniaxially drawn at 90 °C and annealed at the same temperature for 3 and 10 min. Using wide angle x-ray scattering, Raman spectroscopy and differential scanning calorimetry, we probed the effects of WS2 NT addition on the structure of the PLA films at various stages of processing (unstretched, stretching, annealing). We found that 0.6 wt% of WS2 induces the same level of crystallinity in as stretched PLA-WS2 as annealing in neat PLA for 10 min. These data provide useful insights into the role of WS2 NTs on the structural evolution of PLA-WS2 composites under uniaxial deformation, and extend their applicability to situations where fine tuning of PLA crystallinity is desirable.

A Visco-hyperelastic Model for the Thermo-mechanical Behavior of Polymer Fibers

2010 ◽  
Vol 20 (7) ◽  
pp. 1002-1020 ◽  
Author(s):  
G.P. Potirniche ◽  
A. Pascu ◽  
N. Shoemaker ◽  
P.T. Wang ◽  
M.F. Horstemeyer ◽  
...  
Keyword(s):  
Mechanical Behavior ◽  
Penetration Resistance ◽  
Polymer Chains ◽  
Polymer Fibers ◽  
Deformation Characteristics ◽  
Uniaxial Deformation ◽  
The Finite Element Method ◽  
Dynamic Event ◽  
Hyperelastic Model ◽  
Strain Rate Hardening

A visco-hyperelastic model for the thermo-mechanical behavior of polymer yarns is presented. The model assumes that the stress in a yarn during uniaxial deformation results from the superposition of strain rate hardening effects and the softening caused by filament damage. The filament damage accounts for the fracture of polymer chains and the failure of inter-chain bonds. The constitutive model was implemented in the finite element method as a 1D rope element, and was applied to the study of nylon 6.6 and Kevlar ® 29 behavior. Numerical simulations of fabrics subjected to ballistic impact were performed, and the model is shown to predict the fabric penetration resistance and the deformation characteristics during the dynamic event.

A neutron diffraction and modeling study of uniaxial deformation in polycrystalline beryllium

2003 ◽  
Vol 34 (7) ◽  
pp. 1439-1449 ◽  
Author(s):  
D. W. Brown ◽  
M. A. M. Bourke ◽  
C. N. Tomé ◽  
R. Varma ◽  
T. M. Holden ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Uniaxial Deformation ◽  
Modeling Study

Thermally stimulated shrinkage forces in oriented polymers: 2. Time dependence

Polymer ◽  
1985 ◽  
Vol 26 (7) ◽  
pp. 1019-1024 ◽  
Author(s):  
M. Trznadel ◽  
T. Pakula ◽  
M. Kryszewski
Keyword(s):  
Time Dependence ◽  
Oriented Polymers

Efficiency of H center stabilization in alkali halide crystals at low-temperature uniaxial deformation

2020 ◽  
Vol 46 (12) ◽  
pp. 1165-1169
Author(s):  
N. Zhanturina ◽  
L. Myasnikova ◽  
K. Shunkeyev ◽  
A. Maratova ◽  
A. I. Popov
Keyword(s):  
Low Temperature ◽  
Alkali Halide ◽  
Uniaxial Deformation ◽  
Alkali Halide Crystals
Sign in / Sign up

Export Citation Format

Share Document