Initial Young s modulus

The effect of gas compression on the uniaxial compression stress-strain curve of closed-cell polymer foams was analysed. The elastic contribution of cell faces to the compressive stress-strain curve is predicted quantitatively, and the effect on the initial Young s modulus is said to be large. The polymer contribution was analysed using a tetrakaidecahedral cell model. It is demonstrated that the cell faces contribute linearly to the Young s modulus, but compressive yielding involves non-linear viscoelastic deformation. 3 refs. 

Figure 16 Comparison of the dimensionless force Y and fractional deformation of a single 163 pm diameter ion-exchange resin particle (DOWEX 1X8-200, Sigma-Aldrich, UK) obtained by diametrical compression and by numerical simulation using the Tatara non-linear elastic model. E0n represents the initial Young s modulus at zero strain (data provided by Dr T. Liu).

Initial niodidus. This term is intended as initial Young s modulus and is the ratio of specific stress (N tex) to fractional strain along the axis of the stress-strain curve in the Hookean region, with starting point being zero stress and zero strain. This is illustrated in... 

The initial Young s modulus of the fibers, calculated from the slope of the load-elongation curve, has a mean value of about 4 x 103 g/tex/100% extension. The value for any particular group of fibers will, of course, be dependent on the linear density, to some extent, owing to the dependence of tenacity values on this factor. 

Failure in these experiments was defined by a 10 percent reduction in secant modulus compared with the initial Young s modulus. 

Results obtained by these workers for the initial Young s modulus and ultimate tensile strength of cfrc are shown in Figures 15.4 and 15.5. 

Figure 15.4 Initial Young s modulus of continuous carbon fiber reinforced cement. Source Reprinted from Aveston J, Mercer RA, Sillwood JM, Conference Proceedings Composites Standards Testing and Design, NPL 1974, IPC Science Technoiogy Press, 93-103, 1974.

Initial Young s modulus of adhesives at various temperatures... 

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