| The braking effect of automobile is determined by the performance of friction materials.The driving safety and quality of vehicle are determined by the performance of friction materials.The purpose of research on automobile brake pads is to brake safely.Brake pads are required to have stable friction coefficient,high wear resistance and excellent mechanical and physical properties.In order to keep pace with the development of the automobile industry,the research of high-performance brake friction material has become a current hot topic.In order to providing experimental and theoretical basis for developing highperformance friction materials,this dissertation used the orthogonal design method to design the test formula.The phenolic resin-based friction material specimens reinforced with different contents of non-metallic fillers were prepared by one-step hot pressing.The effects of zircon,calcium sulfate whisker,wollastonite and silica on the wear property and mechanism of friction materials were investigated.The Rockwell hardness,shear strength,friction and wear property of the friction materials were tested.The effects of various variables on Rockwell hardness,shear strength,Friction factors and wear rate of the samples were analyzed by the range of analysis method,and the best test formula was screened out by fuzzy comprehensive evaluation.By observing the unworn surface and worn surface of the friction material specimens,the following conclusions were drawn.The Rockwell hardness value of the friction material increases as the content of the non-metallic filler increases.The shear strength of the friction material is between 12.5 and 16 MPa.Compared with Calcium and Zircon,zircon and wollastonite have greater influence on the Rockwell hardness of friction materials.With the increase of zircon content,Rockwell hardness first increases and then decreases.Calcium sulfate whisker has little effect on Rockwell hardness of friction materials.Calcium sulfate whisker has the greatest influence on the shear strength of friction materials.Zircon has a great influence on the friction coefficient of friction materials.The friction coefficient of the friction material increases first and then decreases as the zircon content increases.Non-metallic filler zircon and wollastonite have a greater influence on the wear rate of friction material samples.Material is quickly worn.As the content of the non-metallic filler changes,the friction surface morphology of the sample is different.Because of affected by many factors,the deformation and damage of the friction materials were complex,and the type of friction and wear of the sample was constantly changing.After the working temperature of the sample increased,the organic matter in the friction material decomposed,the adhesiveness of the binder deteriorated,and resulted in the wear and the wear rate increasing.The mechanical strength analysis,friction and wear performance analysis and fuzzy evaluation analysis of friction material samples were considered,sample T10 formula has the best comprehensive performance.In the T10 test formulation,the non-metallic filler zircon accounted for 5%,the calcium sulfate whisker accounted for 4%,the wollastonite accounted for 8%,and the silica accounted for 3.5%. |
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