Dynamic mirror deformations

FIGURE 2. Dynamic filtered deformation electron-density distribution of cyclopropane (1). Sections (a) in the ring plane and (b) in the crystallographic mirror plane, perpendicular to the ring plane. Contours are at 0.05 e A 3 intervals, dashed lines represent negative areas. Reproduced by permission of the International Union of Crystallography from Reference 23b... 

With the geometrical details of the specimens, including the initial crack length a, the physical crack length augmented to account for crack tip plastic deformation (the fracture mirror length) aBs> the dynamic yield stress o-y and the dynamic flexural modulus E, the fracture mechanics parameters Ki, Ju and can be calculated [OlGre]. 

Most of the various types of dynamic methods described in preceding chapters have been applied to fibers. The simplest principle, that of direct measurement of sinusoidally varying stress and strain, has been employed below 0.5 Hz by mechanical deformation and optical recording of both stress and strain with rotating mirrors, somewhat in the manner of the corresponding device of Roelig for soft rubberlike polymers (Chapter 6). The Rheovibron of Takayanagi is well adapted to measurements on fibers. At lower frequencies (down to 10 Hz) an instrument... 

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