Optimization of pore structure and wet tribological properties of paper-based friction materials using chemical foaming technology

Abstract

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 cm3/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.

Improving mechanical and tribological properties of carbon fabric/resin laminated composites by carbon fiber powder

“…As a wear-resistant part, the braking or transmission efficiency of CFRC is critical, therefore, it is required to reduce the wear rate while maintaining the stability of the friction coefficient. 18,19,39 Under the conditions of continuous friction at 150 N, 500 t/min for 60 min, the coefficient of friction and wear rate of composites were studied. Figure 9A,B shows the trend of friction coefficients over time and wear rates for different specimens.…”

“…It is worth noting that the water deposition method is operated by a paper shaper, which realizes the uniform dispersion of CFP on the surface of carbon fabric. 18 Li et al 19 used a paper shaper to achieve uniform deposition of mixed powder. Ma et al 20 had efficiently prepared paper-based friction materials by using a sheet shaper, which were uniformly mixed and dispersed.…”

“…But the various components cannot achieve satisfactory uniformity with the resin solution through blending and stirring. It is worth noting that the water deposition method is operated by a paper shaper, which realizes the uniform dispersion of CFP on the surface of carbon fabric 18 . Li et al 19 used a paper shaper to achieve uniform deposition of mixed powder.…”

Organic–inorganic interface enhancement for boosting mechanical and tribological performances of carbon fiber reinforced composites

“…In virtue of high strength, chemical stability and lightweight, carbon fiber reinforced composites (CFRP) have attracted extensive concern on aerospace, vehicles, and heavy-loading fields. [1][2][3][4][5][6][7] With the rapid development of equipment manufacturing, more rigorous requirements have been put forward for related performances of the composites. However, the drawbacks including surface smooth and chemical inertness of carbon fibers would result in poor interface compatibility between fibers and resin matrix.…”

“…In virtue of high strength, chemical stability and light‐weight, carbon fiber reinforced composites (CFRP) have attracted extensive concern on aerospace, vehicles, and heavy‐loading fields 1–7 . With the rapid development of equipment manufacturing, more rigorous requirements have been put forward for related performances of the composites.…”