INFLUENCE OF TEMPERATURE AND MATERIAL AGEING PROCESSES ON THE POWER CHARACTERISTICS OF POLYMERIC CAR ABSORBING DEVISES

Improving the dynamic qualities, traffic safety and increasing the inter-repair mileage of cars are urgent tasks of car-building industry. The most dangerous loads acting on the car are longitudinal loads during emergency driving modes, to reduce which inter-car shock absorbers (absorbing devices) are provided; their effectiveness must be ensured throughout the whole car life. The performance of polymer car absorbing devices depends primarily on the durability of the polymer, which is a kinetically activated process accelerated by repeated deformations and elevated temperature. The mechanism of the material ageing process depends on the structure of the material. Based on experimental laboratory studies and comparative field tests, ageing of elastomers of different classes have been identified, the dependences of the power characteristics of R-5P absorbing apparatus with two types of solid elastomer (based on rubber and a mixture of elastic thermoplastic with polyvinyl chloride plastic) have been constructed at normal and low temperatures, as well as after 6 years of operation. Recommendations are given to increase the resistance to crystallization and to ageing of polymer elements of absorbing devices. It is advisable to use the characteristics obtained in the paper when modeling the operation of absorbing devices with a solid elastomer, taking into account the operating time.