Abstract:Cu-based friction material were prepared by powder metallurgy technology with natural flake graphite and phenolic resin coated graphite as lubricating components. The effects of graphite surface modification on the microstructure, physical properties, mechanical properties and friction and wear properties of Cu-based friction materials at different braking speeds were studied. The results show that, compared with natural flake graphite/copper-based friction materials, the Cu-based friction materials with resin-coated graphite powder have more uniform graphite distribution, denser copper matrix, higher density, lower porosity, higher flexural strength and compressive strength. When the braking velocity is 5 500 r/min, the wear extent of the phenolic resin-coated graphite/Cu-based friction material is reduced by 24%, the matching plates wearing capacity is reduced by 40%, and the braking time is shortened by 11%. Compared with the natural flake-graphite, the deformation and failure of the resin coated graphite material decreases obviously, and the friction and wear properties of the resin coated graphite material increases.
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