Normalized stress relaxation behaviors of SBR, NBR, NR and EPDM synthetic rubber species

Rubber-like materials are used in different application areas considering the developing technology. However, inelastic properties such as stress relaxation, which prevent the mechanical properties of such materials from being fully understood. In addition, the lifetimes of rubber-type materials with different elongation rates can be obtained by normalizing the stress-time data obtained from the stress relaxation test of the material and drawing it on a 0-1 stress scale. In this study, normalized stress relaxation tests were performed using four types of rubber, three hardness values and two different procedures. As a result, although the increase of hardness decreased the tensile value by 9%, it was observed that the increase in tensile values between the procedures was at the maximum of 7.3% i n t he N R r ubber m aterial a nd i n t he p re-procedural state. Therefore, applying preliminary procedures before the experiments increases the lifetimes of the materials to a certain extent depending on the material characteristics.