▎ 摘　　要

NOVELTY - Polishing liquid for potassium dihydrogen phosphate (KDP) crystal is a non-aqueous chemical mechanical polishing liquid composed of abrasive grain, reactant, additive, organic solvent, and deionized water, where the polishing liquid reactant is at least one of potassium hydroxide, potassium carbonate, potassium bicarbonate, where the mass ratio in the polishing liquid is 0.02-0.10%, it chemically react with the KDP crystal as an acid salt to form product layers dipotassium phosphate and tripotassium phosphate on the crystal surface, the abrasive particles of the polishing liquid are at least one of silicon dioxide, ceric oxide, titanium dioxide and copper oxide, the mass ratio in the polishing liquid is 0.25-2 wt.%. The polishing liquid additive is graphene oxide, where the mass ratio in the polishing liquid is 0.02-0.20 wt.%. USE - The polishing liquid for potassium dihydrogen phosphate crystal is used in high power laser weapon, inertial confinement nuclear fusion device and other countries important strategic equipment. ADVANTAGE - The method rapidly removes macroscopic processing texture and brittle damage produced by wire cutting through the micro-cutting effect of the efficient abrasive particles on the surface of the consolidated abrasive pad, divides grinding into two stages, uses mechanical action of abrasive particles to remove the material, reduces surface roughness of the crystal to the nano level under low pressure, is not easy to cause surface damage, and has high processing efficiency. DETAILED DESCRIPTION - Polishing liquid for potassium dihydrogen phosphate (KDP) crystal is a non-aqueous chemical mechanical polishing liquid composed of abrasive grain, reactant, additive, organic solvent, and deionized water, where the polishing liquid reactant is at least one of potassium hydroxide, potassium carbonate, potassium bicarbonate, where the mass ratio in the polishing liquid is 0.02-0.10%, it chemically reacts with the KDP crystal as an acid salt to form product layers dipotassium phosphate and tripotassium phosphate on the crystal surface, the abrasive particles of the polishing liquid are at least one of silicon dioxide, ceric oxide, titanium dioxide and copper oxide, the mass ratio in the polishing liquid is 0.25-2 wt.%. The polishing liquid additive is graphene oxide, where the mass ratio in the polishing liquid is 0.02-0.20 wt.%, the effect of deionized water in the polishing liquid is to dissolve in time the salts that are soluble in water and insoluble in alcohol after the chemical reaction to prevent the product from remaining on the surface of the workpiece and gradually accumulating to affect the polishing quality, the mass ratio in the polishing solution is 5-30%, the non-toxic organic solvent in the polishing liquid is used as the dispersed phase to avoid the deliquescent layer caused by the KDP crystal dissolution rate being too fast. An INDEPENDENT CLAIM is also included for processing high-efficiency grinding and polishing of KDP crystals, comprising (1) coarse grinding, quickly removing the damage and processing texture produced by the cutting stage, using organic solvents as the grinding liquid, where the grinding pad is made of diamond-bonded abrasive pads, wire cutting, grinding the KDP crystal sample, the grinding time is 5-30 minutes, the grinding pressure is 1-5kPa, and the grinding disc speed is 50-100 revolutions/minute, (2) fine grinding to remove the pits and scratches produced in the rough grinding stage, using an organic solvent as the grinding liquid, and the grinding pad is a diamond-bonded abrasive pad, grinding the KDP crystal sample, where the grinding time is 5-20 minutes, the grinding pressure is 1-4kPa, and the grinding disc rotation speed is 40-80 revolutions/minute, (3) polishing, using IC1000 polishing pad and non-aqueous chemical mechanical polishing liquid to polish the KDP crystal, where the polishing time is 8-30 minutes, and the polishing pressure is 1-3kPa, the speed of the polishing disc is 40-80 revolutions/minute, the polishing process achieves material removal on the crystal surface by balancing the chemical action of reactants, the dissolution of deionized water, and mechanical action of abrasive grains, removing the scratches produced by the grinding process, quickly reducing the surface to nano-level roughness to realize the ultra-precision processing of crystals, and (4) cleaning, polishing the KDP crystal with a polishing cleaning solution on a polishing machine, and immersing the KDP crystal in absolute ethanol for ultrasonic cleaning.