FIXATION OF THREE-DIMENSIONAL STATES OF DEFORMATION IN POLYMERS BY IONIZING RADIATION. SEARCH FOR NEW POLYMERIC MATERIALS

摘要

The fixation of three-dimensional states of deformation in polymers allows the analysis of "special states" of elastic stresses even in the interior of complex constructional units and machine parts. This is the reason for the fact that in spite of the development of modern experimental methods of the analysis of deformation, which are in general restricted to the deformation of the surface of the bodies, the classical "photoelasticity" is still an adequate procedure for solving technical problems. However there are several restrictions on the applicability of the presently used procedures. A potential way to overcome these restrictions is the use of ionizing radiation, which in several polymeric materials causes a more or less perfect fixation of three-dimensional states of deformation. The search for suitable polymers includes the modification of well-known materials like epoxy resins as well as the application and development of materials not yet used in this field of engineering. Preliminary results of the search for such new materials are presented. In selected polymers the stress-optical constant f_σ (S) typically increases with dose, whereas the optical creep behaves ambiguous on irradiation.