Research on Tribological Properties and Viscoelasticity of EPDM Rubber in the Main Drive Sealing System of Shield Machine

The tribological properties and wear mechanisms of EPDM with different carbon black contents under dry friction conditions are studied on an UMT Tribolab friction and wear tester. The variation of carbon black content in EPDM does not lead to the formation of new compounds. However, it significantly improves the shore hardness and tribological properties of EPDM. In addition, significant stick-slip phenomenon occurs during the wear process of EPDM with different carbon black content. During the wear process of EPDM, there are both adhesive wear and abrasive wear, and adhesive wear is the main wear form. Therefore, the results reveal the relationship between carbon black content and tribological properties of EPDM, which can contribute to improve the tribological properties of EPDM.

Ballistic tests of double-based propelling charges with different carbon black content

Nitrocellulose and nitroglycerin are the main components of double-base propellants comprising up to 95% of their total mass. A chemical stabiliser and a burn rate modifier are required components, added in amounts of several percent. The study analyses the effect of carbon black content, contributing less than 1% of the propellant mass, on the burning rate of differently shaped propelling charges. The experiments, carried out on high energetic, double-base propelling charges, showed that the carbon black content significantly affects the burning rate of the propelling charge in the rocket motor chamber.

Влияние содержания технического углерода на фазовый состав и электропроводность полимерного композита

We investigated the effect of carbon black on the phase composition in a composite material based on ethylene vinyl acetate. The existence of an additional, and more high-temperature polymer crystal phase, the relative proportion of which is directly related to the carbon black content, was found. It is shown that peroxide saturation significantly affects the polymorphism of the composite and its electrical conductivity.