The invention relates to a method for improving
hardness of a cover plate, which comprises the following steps: pretreating the surface of the cover plate to remove oil
stain and dust on the surface; a
titanium nitride layer is sprayed on the surface of the cover plate, and after the
titanium nitride layer is sprayed,
residual stress in the
titanium nitride layer is eliminated through an annealing process; carrying out curing treatment on the cover plate; wherein the technological parameters for spraying the
titanium nitride on the surface of the cover plate comprise that the
powder feeding amount is set to be 30-40 g / min, the
electric power is set to be 20-40 KW, the
argon gas flow is set to be 4-5 L / min, the
hydrogen gas flow is set to be 1-2 L / min, the spray gun
voltage is set to be 50-55 V, and the spray gun current is set to be 200-300 A. Spraying is conducted on the surface through
plasma spraying equipment or
electric arc spraying equipment, the spraying process is controlled, and the
hardness of the cover plate can be improved. After spraying, heating curing or
ultraviolet curing is carried out, and it is ensured that the
coating can be firmly attached to the surface of the cover plate after curing. Substances such as
titanium nitride are sprayed on the surface of the cover plate, so that the
hardness of the cover plate is effectively enhanced.