Super coarse grain cemented carbide

According to the grain size grading standard Sandvik, coarse grained cemented carbide grain size is 3.5 ~ 4.9 microns, super coarse grain cemented carbide grain size is 5.0 ~ 7.9 microns.

Oildrilling, Rock Auger Bullet Teeth, coal Auger Teeth, Carbide Teeth,Rock Auger Teeth, Bullet Teeth for Augers stamping die, cold pavement milling planer roll and other widely used in the coarse grain and coarse grain cemented carbide. Low cobalt coarse grain and high cobalt fine grain cemented carbide have become the development direction of cemented carbide. Low cobalt coarse grain of alloy design principle is: the WC grain size, specific surface area is small, thickening of cobalt in the alloy layer, so as to improve the impact toughness of alloy. The cobalt content in the alloy decreases, the increase of WC content in the alloy, improve the alloy wear resistance. Low cobalt coarse grain alloy combination makes the alloy good toughness, high abrasion resistance.

Grain size of coarse grained cemented carbide size depends on the size of WC powder grain size.

Aluminothermy is a production of coarse grain WC (tungsten carbide) special methods. It will tungsten concentration, rolled steel scale (Fe3O4), aluminum powder, CaC2 and other ingredients, add a small amount of potassium perchlorate do lead content. Material exothermic reaction, temperature up to 2500 ℃ ~ 3000 ℃, after the reaction with furnace cooling. Products, such as the upper for potassium calcium aluminate slag for lower metal iron containing WC. About iron contains WC65 %, iron after crushing, cleaning with hot sulfuric acid and hydrochloric acid solution dissolve to iron, single crystal WC particles.

Preparation of coarse grained cemented carbide, want to reduce the efficiency of ball mill and broken as far as possible, improve the mixture, so as to avoid the WC grain is too broken. In practical production increase grinding ball diameter, cut the ball material ratio, shortening the time of ball mill and other methods to reduce the efficiency of ball mill and broken, improve the efficiency of hybrid. Microstructure of coarse grained cemented carbide WC average grain size 7 microns the heavy rain.