The invention provides a roughing solution for
a diamond-
copper composite and a surface
nickel plating method of the
diamond-
copper composite. The roughing solution is composed of, by weight, 1%-10% of
nitrite, 1%-10% of strong base, 0.2%-0.6% of
alcohol amine, 0.1%-0.8% of
carbamide peroxide, 0.1%-0.6% of ferrate and 78%-97.6% of water. The surface
nickel plating method comprises the steps that the surface of the
diamond-
copper composite is subjected to roughing, oil removal, activation, acid
pickling and chemical
nickel plating in sequence, and according to roughing, chemical roughing is carried out on the
diamond-copper composite in the roughing solution. Strong oxidant and strong base are mixed in the roughing solution, so that the problem of a copper
biting reaction existing in traditional acidic roughing
solution treatment is solved, impurities on the surface of the diamond-copper composite can be oxidized and dissolved, and various organic substances and inorganic substances can be adsorbed; therefore, the effect that the surface of the diamond-copper composite is clean, roughed and hydrophilic can be achieved, and the
plating efficiency and quality are improved.