The analysis of the influential parameters that cause particles formation during the braking process: A review

Abstract

The braking system is one of the important systems from the aspect of vehicle safety, but it is also one of the systems that has a significant impact on the environment. Brakes are considered to be a source of non-exhaust particles, that is sources that create particles by the wear of the elements that are in contact with each other, and in this case, the brake friction elements (brake pads and rotating disc). Such particles often contain heavy metals that are part of the friction elements. There are a number of influencing factors that can affect the wear of the friction elements and increase the concentration of the formed particles. Laboratory methods of testing wear and particle formation, road tests and various simulations of brake wear are most often used for testing. In this paper, a review of methodologies for testing the formation of particles from the braking system, the materials used in the composition of the friction elements of the brake, as well as factors affecting the wear rate and concentration of particles of different sizes, based on the conclusions of other authors is presented. Based on this review, it can be concluded which quantities and factors need special attention during further research in the mechanism of formation of non-exhaust particles whose source is the vehicle braking system.