Paper-based friction materials are porous materials that exhibit anisotropy;they exhibit random pore sizes and quantities during their preparation,thereby rendering the control of their pore structure difficult.Compos...Paper-based friction materials are porous materials that exhibit anisotropy;they exhibit random pore sizes and quantities during their preparation,thereby rendering the control of their pore structure difficult.Composites with different pore structures are obtained by introducing chemical foaming technology during their preparation to regulate their pore structure and investigate the effect of pore structure on the properties of paper-based friction materials.The results indicate that the skeleton density,total pore area,average pore diameter,and porosity of the materials increase after chemical foaming treatment,showing a more open pore structure.The addition of an organic chemical foaming agent improves the curing degree of the matrix significantly.Consequently,the thermal stability of the materials improves significantly,and the hardness and elastic modulus of the matrix increase by 73.7%and 49.4%,respectively.The dynamic friction coefficient increases and the wear rate is reduced considerably after optimizing the pore structure.The wear rate,in particular,decreases by 47.7%from 2.83×10^(−8) to 1.48×10^(−8)cm^(3)/J as the foaming agent content increases.Most importantly,this study provides an effective method to regulate the pore structure of wet friction materials,which is conducive to achieving the desired tribological properties.展开更多
基金This research was supported by the National Natural Science Foundation of China(Nos.51872176 and 52172102)the Shaanxi Key Industry Innovation Chain Project(No.2021ZDLGY14-04)+1 种基金the Science Fund for Distinguished Young Scholars of Shaanxi Province(No.2019JC-32)the Fundamental Research Funds for the Central Universities(No.G2020KY05130).
文摘Paper-based friction materials are porous materials that exhibit anisotropy;they exhibit random pore sizes and quantities during their preparation,thereby rendering the control of their pore structure difficult.Composites with different pore structures are obtained by introducing chemical foaming technology during their preparation to regulate their pore structure and investigate the effect of pore structure on the properties of paper-based friction materials.The results indicate that the skeleton density,total pore area,average pore diameter,and porosity of the materials increase after chemical foaming treatment,showing a more open pore structure.The addition of an organic chemical foaming agent improves the curing degree of the matrix significantly.Consequently,the thermal stability of the materials improves significantly,and the hardness and elastic modulus of the matrix increase by 73.7%and 49.4%,respectively.The dynamic friction coefficient increases and the wear rate is reduced considerably after optimizing the pore structure.The wear rate,in particular,decreases by 47.7%from 2.83×10^(−8) to 1.48×10^(−8)cm^(3)/J as the foaming agent content increases.Most importantly,this study provides an effective method to regulate the pore structure of wet friction materials,which is conducive to achieving the desired tribological properties.