Investigation of the usage of organic waste products in composite brake pads

The lining, which is a composite friction material, is the main component of the brake system that plays an important role in the braking performance. In order to investigate the mechanical and tribological behavior of the pads and to improve the braking performance, many studies have been carried out on the pad composition and production parameters, and the researches are continuing. The pads produced are expected to be economical, environmentally friendly and not endanger human health. For this reason, the use of organic waste products has increased as alternative to the materials used in the composite content. In this study, 16 pad samples with different contents were produced by using five types of materials, namely corn husk, flax, hemp, coconut and bamboo powder (5, 10 and 15 wt.%). The samples were produced by powder metallurgy method, which included powder mixing, preforming and hot pressing processes, respectively. The specific wear amount and friction coefficient of the samples were obtained by performing experiments on a test device with a gray cast iron disc. Physical properties such as hardness, density and roughness of the lining samples were determined. After the friction test, the microstructure of the worn surfaces of the samples was examined by Scanning Electron Microscope (SEM). In addition, chemical analyzes of the worn surfaces were obtained by Electron Energy Distribution Spectrometer (EDS). The result of the study showed that the samples containing organic waste material exhibited good behavior in terms of friction performance. The best coefficient of friction values were observed in samples containing %10 coconut, flax, hemp and bamboo and %5 flax.