Research On Thermal Structural Coupling Characteristics And Reliability Of YSZ TBC Disc Brake For Kilometer Deep Mine Hoist

At present,most of the coal mines in China are shallow wells,which are 500-800m deep to the surface.The buried depth of coal resources is about 1000-2000m,which accounts for 53%of the total reserves.The kilometer deep well hoisting system must be used.Disc brake is the most critical safety equipment of hoist,and brake failure will lead to serious accidents.Research on disc brake with high safety and high reliability can provide important guarantee for safe and reliable operation of deep well high-speed and large inertia hoist.Therefore,on the basis of TBCs technology and reliability theory,this paper studies the friction coefficient,wear resistance and thermal deformation resistance of YSZ TBC brake disc,constructs the thermal structure coupling model of disc brake,and carries out the reliability evaluation under emergency braking,which verifies the feasibility of YSZ TBC applied to hoist disc brake.The research contents of this paper are as follows:(1)YSZ with Y₂O₃ doping concentration of 5wt%,8wt%and 10wt%was selected as coating material,and the brake disc material was used as substrate to prepare samples.The friction and wear tests were carried out under different friction pressure and friction speed,and the friction and heat insulation performance of samples with different doping concentration was compared and analyzed,and the influence of different test parameters on the friction and wear performance was studied.(2)Combined with the properties of coating material with the best friction and heat insulation performance,the temperature field simulation analysis of uncoated brake disc and coated brake disc under emergency braking condition was carried out respectively;the radial and circumferential temperature field distribution rules of uncoated brake disc and coated brake disc were compared and analyzed,and the effect mechanism of thermal barrier coating on the temperature change of brake disc under emergency braking was studied.(3)Combined with Latin hypercube design of experiment and Kriging method,the nonlinear mapping model between the random parameters of brake disc and the maximum temperature of brake disc surface is constructed;combined with saddle point approximation theory,the reliability evaluation of uncoated brake disc and coated brake disc under emergency braking condition is carried out,and the effect of thermal barrier coating on the reliability improvement of brake disc is compared and analyzed.