Studies of radiation effects on polymers being conducted at the Convair-Fort Worth Nuclear Facility include engineering tests and fundamental research. The engineering tests are divided into two broad categories, dynamic and static.
While both static and dynamic tests are necessary, dynamic tests give results which provide a better basis for the interpretation of changes with respect to the application of the material. Dynamic tests also supply valuable data in the support of lundamental research and development of new materials. However, some electrical problems arise when dynamic tests are conducted in a reactor field. The radiation field can cause errors in electrical signals through either temporary electrical effects or permanent radiation damage to the test apparatus. The dynamic test assembly must be designed to avoid these problems or minimize the errors.
The three dynamic tests described in this report were designed for the determination of (1) stress relaxation of rubber, (2) the modulus of rigidity of honeycomb sandwich panels by the plate shear method, and (3) the dynamic modulus of elasticity ol rigid plastics by the resonance method. Some of the theory, a description ol the lest gear, and an interpretation of the results of tests performed thus far are presented.