Method for preparing ultra-coarse grain cemented carbide by flexible ball milling technology

The invention discloses a method for preparing ultra-coarse grain cemented carbide by flexible ball milling technology, which comprises the following steps: firstly premixing ultra-coarse WC powder and Co powder for 0.5-2 h with a rotating speed of 6-12 rpm, wherein the Fisher particle size of the WC powder is 18.0-22.0 microns; performing mild ball milling of the premixed powder, adding liquid grinding mediums and a forming agent, wherein the grinding ball material is WC-Co cemented carbide with a diameter of 6-10 mm, the ball milling time is 8-24 h, the ball-to-powder ratio is 1.5-3.0:1, the rotating speed is 20-55% of a critical rotating speed; then discharging the slurry in the ball mill, preparing a mixture by spray drying, performing pressing and molding, sintering at a temperature of 1390-1500 DEG C, wherein the prepared ultra-coarse grain cemented carbide has a grain size of 6.0-10.0 microns, a hardness HV 30 of 740-1240, and a porosity of less than A04B00. The invention is simple in process, short in