Hysteresis in Crystallization of Stretched Vulcanized Rubber from X-Ray Data Correlation with Stress-Strain Behavior and Resilience

1940 ◽  
Vol 32 (11) ◽  
pp. 1474-1477 ◽  
Author(s):  
George L. Clark ◽  
Marian Kabler ◽  
Ernest Blanker ◽  
John M. Ball
Keyword(s):  
Data Correlation ◽  
Stress Strain ◽  
X Ray ◽  
Strain Behavior ◽  
Vulcanized Rubber

Hysteresis in Crystallization of Stretched Vulcanized Rubber from X-Ray Data. Correlation with Stress-Strain Behavior and Resilience

1941 ◽  
Vol 14 (1) ◽  
pp. 27-34
Author(s):  
George L. Clark ◽  
Marian Kabler ◽  
Ernest Blaker ◽  
John M. Ball
Keyword(s):  
Normal State ◽  
Previous History ◽  
The Body ◽  
Stress Strain ◽  
X Ray ◽  
Strain Behavior ◽  
Vulcanized Rubber ◽  
Set Up ◽  
Applied Stresses ◽  
Marked Tendency

Abstract 1. For sample H, with high modulus and high resilience, there is a greater crystallizing tendency above 350 per cent for the first cycle and above 400 per cent after previous flexing. 2. Both H and L have narrow loops, which indicate an approach to reversibility in the formation and deformation of crystalline regions above 400 per cent for the first and later cycles. 3. The crystallization of H is greatly enhanced above 400 per cent after the first cycle of stretching and retraction; L remains essentially unchanged by previous history over this range; this is analogous to the much greater change in the stress-strain loop from the first to third cycles for H, as compared with L. 4. At elongations below 400 per cent for the first cycle and 350 per cent for subsequent cycles, L has a far greater hysteresis or tendency to retain the crystalline arrangement, and this greatly increases after the first cycle, so that the fiber interferences persist on retraction to elongations 150 per cent below the elongation required for institution of organization on extension of the sample. Sample H is considerably more consistent in its behavior over the lower elongations, and between the first and later cycles. In other words, the tendency of H to return to the normal state on release of a deforming force is clearly evident, whereas L shows a marked tendency to retain a structure once set up. If resilience is the property of an elastic body related to the percentage of the potential energy introduced by applied stresses which is returned as work when the body returns to its original shape and size upon release of the stresses, then these x-ray data would seem to be consistent with the higher resilience of H; for ordinary measurements of resilience are evidently related to the lower ranges of deformation over which H returns to its normal state (disorder of macromolecules as in a liquid) so much more easily than L.

scholarly journals Evaluation of stress-strain behavior of surface treated steels by X-ray diffraction

2012 ◽  
Vol 2 (1) ◽  
Author(s):  
Luis Coelho ◽  
A. Batista ◽  
J. Nobre ◽  
M. Marques
Keyword(s):  
Yield Strength ◽  
Plasma Nitriding ◽  
Nitrided Layer ◽  
Experimental Methodology ◽  
X Ray Diffraction ◽  
Stress Strain ◽  
X Ray ◽  
Strain Behavior ◽  
Four Point Bending ◽  
Nitride Layers

AbstractX-ray diffraction assisted four-point bending method (XRDABM) enables to analyze the evolution of surface stress with the strain during bending of specimens. This experimental methodology was used to characterize the stress-strain behavior of two plasma nitriding steels, DIN 40 Cr Mn Mo 7 and DIN 32 Cr Mo V 13, with gradients of mechanical properties across the surface layers, allowing the characterization of the in-depth evolution of the local yield strength in the nitrided layer. The results show a significantly increase of the yield strength of the nitride layers and a good agreement between the in-depth evolution of the yield strength and the XRD peak breadth for the two nitrided steels.

X-Ray Investigation of the Crystallization of Vulcanized Rubber on Stretching

1948 ◽  
Vol 21 (3) ◽  
pp. 621-626 ◽  
Author(s):  
B. V. Lukin ◽  
V. I. Kasatochkin
Keyword(s):  
Tensile Strength ◽  
Crystalline Phase ◽  
Oxidative Degradation ◽  
Point Of View ◽  
Crystal Formation ◽  
Stress Strain ◽  
X Ray ◽  
Vulcanized Rubber ◽  
Cross Links ◽  
Ray Methods

Abstract 1. x-Ray methods have been used to investigate the amount of crystalline phase in stretched samples as a function of the vulcanization time. 2. Curves relating the percentage of crystalline phase to the vulcanization time have sharply defined maxima. 3. A comparison of the curves relating tensile strength to vulcanization time with the curves of crystal formation shows their analogous character, the position of the maxima approximately corresponding to one and the same vulcanization time. 4. The position of the maxima on the curves of crystal formation is not related to the degree of stretching. 5. The effect of accelerators is to shift the maximum on the curve of crystal formation to the region of short vulcanization times and to increase the percentage of crystalline phase. 6. The curves of crystal formation and of tensile strength, and thus the behavior of the stress-strain curves for various vulcanization times, is interpreted from the point of view of the existence of two processes—the process of forming a network of cross-links by the interaction of rubber with sulfur, and the process of oxidative degradation of the rubber.

Stress Strain Behavior of Steel Fibre Based Concrete in Compression

2012 ◽  
Vol 1 (3) ◽  
pp. 32-38
Author(s):  
Tantary M.A ◽  
◽  
Upadhyay A ◽  
Prasad J ◽  
◽  
...  
Keyword(s):  
Steel Fibre ◽  
Stress Strain ◽  
Strain Behavior

Cord/Rubber Material Properties

1985 ◽  
Vol 58 (4) ◽  
pp. 830-856 ◽  
Author(s):  
R. J. Cembrola ◽  
T. J. Dudek
Keyword(s):  
Finite Element ◽  
Material Model ◽  
Rubber Composites ◽  
Stress Strain ◽  
Element Analysis ◽  
Rubber Layer ◽  
Strain Behavior ◽  
Nonlinear Stress ◽  
Interlaminar Shear ◽  
Mechanics Of Composite Materials

Abstract Recent developments in nonlinear finite element methods (FEM) and mechanics of composite materials have made it possible to handle complex tire mechanics problems involving large deformations and moderate strains. The development of an accurate material model for cord/rubber composites is a necessary requirement for the application of these powerful finite element programs to practical problems but involves numerous complexities. Difficulties associated with the application of classical lamination theory to cord/rubber composites were reviewed. The complexity of the material characterization of cord/rubber composites by experimental means was also discussed. This complexity arises from the highly anisotropic properties of twisted cords and the nonlinear stress—strain behavior of the laminates. Micromechanics theories, which have been successfully applied to hard composites (i.e., graphite—epoxy) have been shown to be inadequate in predicting some of the properties of the calendered fabric ply material from the properties of the cord and rubber. Finite element models which include an interply rubber layer to account for the interlaminar shear have been shown to give a better representation of cord/rubber laminate behavior in tension and bending. The application of finite element analysis to more refined models of complex structures like tires, however, requires the development of a more realistic material model which would account for the nonlinear stress—strain properties of cord/rubber composites.

Compressive stress–strain behavior of steel fiber reinforced-recycled aggregate concrete

2014 ◽  
Vol 46 ◽  
pp. 65-72 ◽  
Author(s):  
Jodilson Amorim Carneiro ◽  
Paulo Roberto Lopes Lima ◽  
Mônica Batista Leite ◽  
Romildo Dias Toledo Filho
Keyword(s):  
Compressive Stress ◽  
Steel Fiber ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Fiber Reinforced ◽  
Stress Strain ◽  
Aggregate Concrete ◽  
Strain Behavior
Sign in / Sign up

Export Citation Format

Share Document