Research on the thermal stress characteristics of self-cooled brake discs of belt conveyors

Equipped with rib groove structure, the self-cooled brakes disc enjoys an excellent heat dispersion and are applied in the belt conveyors with good effect. According to Hooke’s Law, the steady-state thermo-mechanical coupling expression of the brake disc under two-dimensional conditions is deduced, and the solving method of the displacement differential equation is given. Based on the ABAQUS, thermo-mechanical coupling finite element model for self-cooled disc brakes is established and for the structure and load characteristics of the brake discs, three different azimuth paths are defined and the transient thermal stress variations under different paths are obtained. Through the thermal cycling tests of self-cooling brake disc samples at 300 °C, 400 °C, and 500 °C under the condition of heat and water-cooling for 800 times respectively and analyzing the metallographic structure with electron probe microscope, the results have showed that a large amount of graphitized tissue can be precipitated under the high circulating temperature and heating cracks can induced.