▎ 摘　　要

NOVELTY - Brake pad comprises base plate provided with friction block. The friction block includes upper substrate layer, substrate layer and base steel plate contact provided with diamond-graphene composite layer for preventing from friction. The diamond-graphene composite layer single crystal lamellar structure which is formed by nanodiamonds alkenyl sp2 hybridized carbon between the sp3 hybridized carbon of graphen with lattice spacing of 0.21 nm, average particle diameter of nanodiamonds alkenyl lies in the range 20-500 nm. The carbon content of nanodiamonds alkenyl is 99-100%. USE - Brake pad. ADVANTAGE - The brake pad is high abrasion resistance, good thermal conductivity and high hardness. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing diamond-graphene composite layer which involves; (A) selecting average particle diameter 10-20 nm, 100-250 nm, 350-500 of three types of nano diamond alkenyl; (B) mixing three types of nano-diamond in weight ratio of 1-2:3-4:4-5; (C) adding 6 wt.% of aqueous sodium silicate solution, with stirring for 30-60 minute; (D) baking to obtain diamond-alkenyl layer; and (E) bonding diamond-alkenyl layer to the friction layer to form a friction block which is bonded to the base plate to obtain diamond-graphene composite layer. DESCRIPTION OF DRAWING(S) - The drawing shows schematic view of brake pad.