Role of the Entangled Amorphous Network in Tensile Deformation of Semicrystalline Polymers

2003 ◽  
Vol 91 (9) ◽  
Author(s):  
Yongfeng Men ◽  
Jens Rieger ◽  
Gert Strobl
Keyword(s):  
Tensile Deformation ◽  
Semicrystalline Polymers ◽  
Amorphous Network

Mechanical anisotropy and local ductility in transverse tensile deformation in hot rolled steels: The role of MnS inclusions

2019 ◽  
Vol 744 ◽  
pp. 324-334 ◽  
Author(s):  
Meng Wu ◽  
Wen Fang ◽  
Ruo-Meng Chen ◽  
Bo Jiang ◽  
Hai-Bo Wang ◽  
...  
Keyword(s):  
Tensile Deformation ◽  
Mechanical Anisotropy ◽  
Transverse Tensile ◽  
Hot Rolled

scholarly journals Competition between crystal growth and intracrystalline chain diffusion determines the lamellar thickness in semicrystalline polymers

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Martha Schulz ◽  
Mareen Schäfer ◽  
Kay Saalwächter ◽  
Thomas Thurn-Albrecht
Keyword(s):  
Decisive Role ◽  
Semicrystalline Polymers ◽  
Lamellar Thickness ◽  
Polarization Microscopy ◽  
Polymer Systems ◽  
X Ray Scattering ◽  
Special Cases ◽  
Lamellar Crystals ◽  
Nmr Methods

AbstractThe non-equilibrium thickness of lamellar crystals in semicrystalline polymers varies significantly between different polymer systems and depends on the crystallization temperature Tc. There is currently no consensus on the mechanism of thickness selection. Previous work has highlighted the decisive role of intracrystalline chain diffusion (ICD) in special cases, but a systematic dependence of lamellar thickness on relevant timescales such as that of ICD and stem attachment has not yet been established. Studying the morphology by small-angle X-ray scattering and the two timescales by NMR methods and polarization microscopy respectively, we here present data on poly(oxymethylene), a case with relatively slow ICD. It fills the gap between previously studied cases of absent and fast ICD, enabling us to establish a quantitative dependence of lamellar thickness on the competition between the noted timescales.

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.

Role of coupling microscopic and macroscopic phenomena during the crystallization of semicrystalline polymers

2001 ◽  
Vol 41 (11) ◽  
pp. 1871-1885 ◽  
Author(s):  
N. Prabiiu ◽  
J. Schultz ◽  
S. G. Advani ◽  
K. I. Jacob
Keyword(s):  
Semicrystalline Polymers

The role of dislocations for the plastic deformation of semicrystalline polymers as investigated by multireflection X-ray line profile analysis

2012 ◽  
Vol 125 (6) ◽  
pp. 4150-4154 ◽  
Author(s):  
Florian Spieckermann ◽  
Gerald Polt ◽  
Harald Wilhelm ◽  
Michael Kerber ◽  
Erhard Schafler ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Line Profile ◽  
Profile Analysis ◽  
Semicrystalline Polymers ◽  
Line Profile Analysis ◽  
X Ray

Quantification of Cavitation in Neat and Calcium Carbonate-Filled High-Density Polyethylene Subjected to Tension

2011 ◽  
Vol 133 (3) ◽  
Author(s):  
F. Addiego ◽  
J. Di Martino ◽  
D. Ruch ◽  
A. Dahoun ◽  
O. Godard ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
High Density Polyethylene ◽  
Shape Factor ◽  
Tensile Deformation ◽  
Quantitative Information ◽  
Semicrystalline Polymers ◽  
High Density ◽  
Deformation State ◽  
Microscopic Features ◽  
Void Shape

Cavitation-induced deformation mechanisms in neat semicrystalline polymers, i.e., crazing, and in the derived composites, i.e., particle-matrix debonding, are generally activated during the transition between viscoelastic and viscoplastic deformation stages. However, little quantitative information about the void evolution with the drawing level is to date available in the literature. The objective of this work is to quantify cavitation mechanisms in neat and calcium carbonate-filled high-density polyethylene (HDPE) subjected to tensile deformation. Attention was first focused on the properties of the materials that were assessed by means of a thermogravimetric analyzer, a differential scanning calorimeter, a scanning electron microscope (SEM), and a dynamic mechanical analyzer. In a second step, macroscopic aspects of cavitation were studied by quantifying volume variation of the materials subjected to tension using an accurate optical extensometer (VidéoTraction). Attention was then turned to microscopic features of cavitation through a careful quantification of void density and shape factor by means of a method coupling a SEM with an image analysis procedure. At the two scales of interest, the results demonstrate that (i) the void density generated by crazing in neat HDPE or particle-matrix debonding in the composites gradually increases with the deformation state, (ii) void density induced by debonding is higher than that generated by crazing, and (iii) decreasing particles size causes an increase of void density. We also estimated the void shape factor, that is, ratio between the height and the width of the cavities. In all the studied materials, this parameter starts from a value that is below 1 and increases by a factor of 2 with increasing deformation. Moreover, in the case of the composites, one notes a higher void shape factor compared with the neat material, and particle size does not influence this parameter. The results provided by this paper can be the basis of a physically based model predicting cavitation mechanisms in semicrystalline polymers.

scholarly journals Effect of Discontinuous Yielding on the Strain Hardening Behavior of Fine-Grained Twinning-Induced Plasticity Steel

2021 ◽  
Vol 8 ◽  
Author(s):  
Singon Kang ◽  
Sujin Jeong ◽  
Yeon-Sang Ahn
Keyword(s):  
Strain Hardening ◽  
Tensile Deformation ◽  
Early Stage ◽  
Image Correlation ◽  
Localized Deformation ◽  
Fine Grained ◽  
Cooling Conditions ◽  
Strain Hardening Behavior ◽  
Strain Hardening Rate

The yielding of a high Mn twinning-induced plasticity steel was examined in three fine-grained specimens recrystallized at 700°C for 5 min with different cooling conditions. While the stress-strain curves of furnace-cooled and air-cooled specimens exhibit a stress drop at yielding, the drop was not observed in the water-quenched specimen. A simple analysis of the displacement data indicates the occurrence of localized deformation at the beginning of the plastic deformation in the three tensile specimens with different cooling conditions. The localized deformation of all three specimens was confirmed as Lüders strain by digital image correlation (DIC) analysis. Based on this observation, the role of yielding behavior on the strain hardening rate evolution at an early stage of the tensile deformation was discussed.

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