On using a Weissenberg rheogoniometer for oscillatory testing of stiff materials

Abstract

When the Weissenberg rheogoniometer is used for oscillatory testing on stiff systems and experimental results interpreted in the conventional way, anomalous results occur. These are due to a lack of rigidity in rheogoniometer parts such as the air-bearing rotor, extension piece and lower platen holder, especially the latter. Future experiments on stiff systems will be facilitated by more rigid instrument members. Existing experimental results can be re-interpreted on the basis of the theory given.